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CARNEGIE INSTITUTION

WASHINGTON

YEAR BOOK No. 37

JULY 1, 1937— JUNE 30, 1938

WITH ADMINISTRATIVE REPORTS THROUGH DECEMBER 9, 1938

Published by Carnegie Institution of Washington

Washington, D. C.

1938

JUDD & DETWEILER, INC.

STANDARD ENGRAVING CO.

WASHINGTON, D. C.

CONTENTS

PAGES

Officers and Staff v-x

Organization, Plan, and Scope xi

Articles of Incorporation xii-xiv

By-Laws of the Institution xv-xviii

Abstract of Minutes of the Thirty-ninth Meeting of the

Board of Trustees xix

Abstract of Minutes of the Fortieth Meeting of the Board of

Trustees xx-xxiii

Report of the Executive Committee xxiv-xxv

Aggregate Receipts and Disbursements xxvi

Report of Auditors and Financial Statement xxvii-xxxiv

Report of the President of the Institution 1-65

Reports on Investigations:

Division of Animal Biology 3-103

Department of Embryology 4-34

Department of Genetics 35-72

Nutrition Laboratory 73-83

Tortugas Laboratory 84-103

Geophysical Laboratory 105-136

Division of Historical Research 137-172

Mount Wilson Observatory 173-208

Division of Plant Biology 209-238

Department of Terrestrial Magnetism 239-293

The Atomic-Physics Observatory, Department of Terrestrial

Magnetism, Washington, D. C facing 239

Other Investigations :

Anthropology :

Aberle, Sophie D 295-296

Astronomy :

Boss, Benjamin, Harry Raymond, and Isabella Lange 297-298

Roy, A. J 298

Biology :

Castle, W. E 299-300

Conger, Paul 300-302

Dice, Lee R 302-303

Morgan, T. H., C. B. Bridges, and Jack Schultz 304-309

Application of Research to Problems in Conservation 310-311

Ecology :

Elton, Charles 312

Embryology :

Hertig, Arthur T 313-314

Schultz, Adolph H 314-315

Genetics :

Babcock, E. B 316-318

Burks, Barbara S 318-320

Davenport, Charles B 320-323

Dobzhansky, Th 323-325

Meteorology :

Bjerknes, V 326-328

iii

CONTENTS

Nutrition :

Ritzman, E. G

Sherman, H. C

Vickery, H. B

Palaeography :

Lowe, E. A

Palaeontology, Early Man, and Historical Geology:

Merriam, John C., and Associates

Cressman, L. S

Rogers, Malcolm J

Harrington, M. R

Howard, E. B

Antevs, Ernst

deTerra, H

von Koenigswald, G. H. R

Kellogg, Remington

Stock, Chester

Richards, Horace G

Buwalda, J. P

Hinds, Norman E. A

McKee, Edwin D

Campbell, Ian, and John H. Maxson

Physics :

Committee on Coordination of Cosmic-Ray Investigations

Beagley, J. W

Forbush, S. E

Johnson, Thomas H

Korff, S. A

Millikan, Robert A

Epstein, P. S., and G. W. Potapenko

Committee on Study of the Surface Features of the Moon . . .

Physiology :
Russell, G. Oscar

Psychology :
Ruger, Henry A

St. Augustine Historical Program:

Chatelain, Verne E

Seismology :

California Institute of Technology ,

Office of Publications

Index

PAGES

329-331
331-334
334r-338

339

340-364
341-344
344-345
345-347
347
348
348-351
351-352
352-353
353-355
355-356
356-358
358
35&-359
359-364

365-380
367-368
368-373
373-375
376-378
378-380
381
381-383

384-387

388

389-391

392-395
396-432
433-443

PRESIDENT AND TRUSTEES

PRESIDENT

John C. Merriam*

BOARD OF TRUSTEES

W. Cameron Forbes, Chairman
Walter S. Gifford, Vice-Chairman

Frederic A. Delano, Secretary
Thomas Barbour Walter A. Jessup Elihu Root, Jr.

James F. Bell Frank B. Jewett Henry R. Shepley

Robert Woods Bliss Charles A, Lindbergh William Benson Storey
Frederic A. Delano Alfred L. Loomis Richard P. Strong

Homer L. Ferguson Roswell Miller Charles P. Taft

W. Cameron Forbes Henry S. Morgan James W. Wadsworth

Walter S. Gifford Stewart Paton Frederic C. Walcott

Herbert Hoover John J. Pershing Lewis H. Weed

Executive Committee

W. Cameron Forbes, Chairman

Robert Woods Bliss Walter S. Gifford Frederic C. Walcott

Frederic A. Delano Walter A. Jessup Lewis H. Weed

Jofin C. Merriam*

Finance Committee

Frederic C. Walcott, Chairman

Walter S. Gifford Henry S. Morgan

Alfred L. Loomis Elihu Root, Jr.

Auditing Committee

Frederic A. Delano, Chairman
Homer L. Ferguson William Benson Storey

STANDING COMMITTEES FOR THE YEAR 1939
Committee on Astronomy

Herbert Hoover, Chairman

Walter S. Gifford Elihu Root, Jr.

Roswell Miller William Benson Storey

Committee on Terrestrial Sciences

Frank B. Jewett, Chairman

Frederic A. Delano Henry S. Morgan

Homer L. Ferguson James W. Wadsworth

Committee on Biological Sciences

Lewis H. Weed, Chairman

Thomas Barbour Alfred L. Loomis

James F. Bell Stewart Paton

Committee on Historical Research

Henry R. Shepley, Chairman

Robert Woods Bliss Richard P. Strong

Charles A. Lindbergh Charles P. Taft

* On January 1, 1939, Dr. Merriam becomes President Emeritus, and Dr. Vannevar
Bush succeeds him as President of the Institution.

FORMER PRESIDENTS AND TRUSTEES

PRESIDENTS

Daniel Coit Gilman, 1902-04 Robert Simpson Woodward, 1904-20

TRUSTEES

Alexander Agassiz
George J. Baldwin
John S. Billings
Robert S. Brookings
John L. Cadwalader
William W. Campbell
John J. Carty
Whitefoord R. Cole
Cleveland H. Dodge
William E. Dodge
Charles P. Fenner
Simon Flexner
William N. Frew
Lyman J. Gage
Cass Gilbert
Frederick H. Gillett
Daniel C. Gilman
John Hay
Myron T. Herrick
Abram S. Hewitt
Henry L. Higginson
Ethan A. Hitchcock
Henry Hitchcock
William Wirt Howe
Charles L. Hutchinson
Samuel P. Langley
Wtilliam Lindsay
Henry Cabot Lodge

1904-05
1925-27
1902-13
1910-29
1903-14
1929-38
1916-32
1925-34
1903-23
1902-03
1914-24
1910-14
1902-15
1902-12
1924-34
1924-35
1902-08
1902-05
1915-29
1902-03
1902-19
1902-09
1902-02
1903-09
1902-04
1904-06
1902-09
1914-24

Seth Low 1902-16

Wayne MacVeagh 1902-07

Andrew J. Mellon 1924-37

Darius O. Mills 1902-09

S. Weir Mitchell 1902-14

Andrew J. Montague 1907-35

William W. Morrow 1902-29
William Church Osborn 1927-34

James Parmelee 1917-31

Wm. Barclay Parsons 1907-32

George W. Pepper 1914-19

Henry S. Pritchett 1906-36

Elihu Root 1902-37

Julius Rosen wald 1929-31

Martin A. Ryerson 1908-28

Theobald Smith 1914-34

John C. Spooner 1902-07

William H. Taft 190&-15

William S. Thayer 1929-32

Charles D. Walcott 1902-27

Henry P. Walcott 1910-24

William H. Welch 1906-34

Andrew D. White 1902-16

Edward D. White 1902-03

Henry White 1913-27

George W. Wickersham 1909-36

Robert S. Woodward 1905-24

Carroll D. Wright 1902-08

Besides the names enumerated above, the following were ex-officio mem-
bers of the Board of Trustees under the original charter, from the date of
organization until April 28, 1904: the President of the United States, the
President of the Senate, the Speaker of the House of Representatives, the
Secretary of the Smithsonian Institution, the President of the National
Academy of Sciences.

STAFF OF INVESTIGATORS FOR THE YEAR 1938

PHYSICAL SCIENCES
Advisory Committee on Physical Sciences: F. E. Wright, Chairman

L. H. Adams
W. S. Adams
J. A. Fleming

H. A. Spoehr
J. Stebbins
E. B. Wilson

Geophysical Laboratory

Organized in 1906, opened in 1907; Arthur L. Day, Director 1907-1936.

L. H. Adams, Director
John S. Burlew
Allen Crocker
Joseph L. England
Michael Fleischer
R. E. Gibson
R. W. Goran son
J. W. Greig
J. H. Hibben
Earl Ingerson
F. C. Kracek
C. J. Ksanda

O. H. LOEFFLER

H. E. Merwin
G. W. Morey
E. F. Osborn
Charles S. Piggot
Eugene Posnjak
H. S. Roberts
J. F. Schairer

E. S. Shepherd
George Tunell
W. D. Urry

F. E. Wright
E. G. Zies

Mount Wilson Observatory

Organized in 1904; George E. Hale, Director 1901-1923, Hon. Director 1923-1936.

Walter S. Adams, Director

F. H. Seares, Assistant Director

Alfred H. Joy, Secretary

A. S. King, Supt. Physical Laboratory

J. A. Anderson

Walter Baade

Harold D. Babcock

William H. Christie

Theodore Dunham, Jr.

Joseph Hickox

Edison Hoge

Edwin P. Hubble

Milton L. Humason
Paul W. Merrill
Rudolph Minkowski
Seth B. Nicholson
Edison Pettit
R. S. Richardson
R. F. Sanford
Gustaf Stromberg
A. van Maanen
Olin C. Wilson
Ralph E. Wilson

Department of Terrestrial Magnetism

Organized in 1904; L. A. Bauer, Director 1904-1929.

J. A. Fleming, Director

O. H. Gish, Assistant Director

L. V. Berkner

F. T. Davies

S. E. Forbush

John W. Green

L. R. Hafstad

N. P. Heydenburg

E. A. Johnson

H. F. Johnston

P. G. Ledig

A. G. McNish

R. C. Meyer

Wilfred C. Parkinson

Richard B. Roberts, Fellow

W. J. Rooney

W. E. Scott

S. L. Seaton

K. L. Sherman

H. E. Stanton

Oscar W. Torreson

M. A. Tuve

E. H. Vestine

G. R. Wait

W. F. Wallis

H. W. Wells

vii

DIVISION OF PLANT BIOLOGY: H. A. Spobhb, Chairman

Desert Laboratory, opened in 1903, became headquarters of Department of Botanical Research in 1905.
Name changed to Laboratory for Plant Physiology in 1923 ; reorganized in 1928 as Division of Plant Biology,
including Ecology.

Jens C. Clausen T. D. Mallery

Frederic E. Clements Emmett Martin

Waldo S. Glock H. W. Milner

Wm. M. Hiesey Forrest Shreve

David D. Keck James H. C. Smith

Frances L. Long H. H. Strain

DIVISION OF ANIMAL BIOLOGY: George L. Streeter, Chairman

An administrative grouping made effective in 1935, including activities of the following Departments:

Department of Embryology

Organized in 1914; Franklin P. Mall, Director 1914-1917.

George L. Streeter, Director Margaret R. Lewis

Carl G. Hartman Warren H. Lewis

Chester H. Hetjser Charles W. Metz

Department of Genetics

Station for Experimental Evolution, opened in 1904, was combined with Eugenics Record Office in 1921
to form Department of Genetics. Charles B. Davenport, Director 1904-1934.

A. F. Blakeslee, Director E. C. MacDowell

M. Demerec, Assistant Director James S. Potter

H. H. Laughlin, Assistant Director Oscar Riddle

A. G. Avery Sophia Sattna

R. W. Bates J. P. Schooley

A. Dorothy Bergner Morris Steggerda

B. P. Kaufmann H. E. Warmke

Nutrition Laboratory

Organized in 1907, opened in 1908; F. G. Benedict, Director 1907-1937.

T. M. Carpenter, Acting Director Robert C. Lee

V. CoROPATCHINSKY

Tortugas Laboratory

Established in 1904. Alfred G. Mayor, Director 1904-1922; W. H. Longley, Executive Officer 1924-1937.
Open for marine biological studies during summer months.

D. H. Tennent, Executive Officer

P. S. Conger, Assistant Executive Officer

DIVISION OF HISTORICAL RESEARCH: A. V. Kidder, Chairman

Department of Historical Research was organized in 1903; Andrew C. McLaughlin, Director 1903-1905,
J. Franklin Jameson, Director 1905-1928. In 1930 this Department was incorporated as the Section of
United States History in a new Division of Historical Research.

Section of Aboriginal American Section of Post-Columbian

History American History

Sylvanus G. Morley Robert S. Chamberlain

Earl H. Morris Ralph L. Roys

H. E. D. Pollock France V. Scholes

O. G. Ricketson, Jr. Leo F. Stock

Anna O. Shepard Section of the History of Science
A. Ledyard Smith George Sarton

Gustav Stromsvik Alexander Pogo

J. Eric Thompson Mary Welborn

viii

RESEARCH ASSOCIATES

Ernst Antevs, Climatology Newton B. Drury, Study of Primitive

Marion E. Blake, Archaeology Areas

Benjamin Boss, Astronomy Robert Emerson, Biology

C. B. Bridges, Biology Charlton M. Lewis, Physics

Barbara S. Burks, Genetics F. A. Perret, Geophysics

Alfonso Caso, Archaeology Harry Raymond, Astronomy

Verne E. Chatelain, History Arthur J. Roy, Astronomy

Paul S. Conger, Biology Jack Schultz, Biology

H. deTerra, Archaeology and Palaeontolog}' Harry O. Wood, Seismology

A. E. Douglass, Climatology S. Yamanouchi, Biology

Research Associates Engaged in Post-retirement Studies

F. G. Benedict, Nutrition Charles B. Davenport, Biology
Edmund C. Burnett, History Arthur L. Day, Geophysics

Research Associates Connected with Other Institutions

Sophie D. Aberle (United States Office of Indian Affairs), Anthropology

M. J. Andrade (University of Chicago), Linguistics

E. B. Babcock (University of California), Genetics

I. W. Bailey (Bussey Institute), Plant Biology

J. Bartels (Forstliche Hochschule, Eberswalde), Terrestrial Magnetism

V. Bjerknes (University of Oslo, Norway), Meteorology

G. Breit (University of Wisconsin), Physics.

J. P. Buwalda (California Institute of Technology), Geology and Palaeontology

Ian Campbell (California Institute of Technology), Geology and Palaeontology

W. E. Castle (University of California), Biology

Ralph W. Chaney (University of California), Palaeobotany

S. Chapman (Imperial College, London), Terrestrial Magnetism

A. H. Compton (University of Chicago), Physics

L. S. Cressman (University of Oregon), Archaeology

L. R. Dice (University of Michigan), Biology

Th. Dobzhansky (California Institute of Technology), Genetics

G. Gamow (George Washington University), Terrestrial Magnetism

Ross Gunn (Naval Research Laboratory), Terrestrial Magnetism

W. A. Heidel (Wesleyan University), History of Science

Norman E. A. Hinds (University of California), Geology

Edgar B. Howard (University of Pennsylvania), Archaeology and Palaeontology

J. H. Jeans (Royal Society of London), Astronomy

Thomas H. Johnson (Bartol Research Foundation), Physics

Remington Kellogg (United States National Museum), Palaeontology

S. A. Korff (Bartol Research Foundation), Physics

E. A. Lowe (The Institute for Advanced Study), Palaeography

C. L. Lundell (University of Michigan), Botany

John H. Maxson (California Institute of Technology), Geology and Palaeontology

Edwin D. McKee (United States National Park Service), Geology and Palaeontology

R. A. Millikan (California Institute of Technology), Physics

S. A. Mitchell (University of Virginia), Astronomy

T. H. Morgan (California Institute of Technology), Biology

Robert Redfield (University of Chicago), Anthropology

E. G. Ritzman (New Hampshire Agricultural Experiment Station), Nutrition

Malcolm J. Rogers (The San Diego Museum), Archaeology and Palaeontology

Henry A. Ruger (Columbia University), Psychology

G. Oscar Russell (Ohio State University), Physiology

Henry N. Russell (Princeton University), Astronomy

A. H. Schultz (Johns Hopkins University), Anthropology

H. C. Sherman (Columbia University), Nutrition

Joel Stebbins (University of Wisconsin), Astronomy

Chester Stock (California Institute of Technology), Palaeontology

H. U. Sverdrup (Scripps Institute of Oceanography), Terrestrial Magnetism

H. B. Vickery (Connecticut Agricultural Experiment Station), Physiological Chemistry

G. H. R. von Koenigswald (Bandoeng, Java), Palaeontology

Bailey Willis (Stanford University), Seismology

E. B. Wilson (Harvard University), Climatology

OFFICES OF ADMINISTRATION

January 1, 1939

Vannevar Bush, President

Office of the President

Vannevar Bush, President

Walter M. Gilbert, Administrative Secretary

Samuel Callaway, President's Secretary

Office of Publications

Frank F. Bunker, Editor
Irving M. Grey, Secretary
Dorothy R. Swift, Editorial Assistant

Office of the Bursar

Edmund A. Varela, Bursar

Earle B. Biesecker, Assistant Bursar

ORGANIZATION, PLAN, AND SCOPE

The Carnegie Institution of Washington was founded by Andrew Car-
negie, January 28, 1902, when he gave to a board of trustees an endowment
of registered bonds of the par value of ten million dollars. To this fund
an addition of two million dollars was made by Mr. Carnegie on December
10, 1907, and a further addition of ten million dollars was made by him on
January 19, 1911. Furthermore the income of a reserve fund of about three
million dollars, accumulated in accordance with the founder's specifications
in 1911, is now available for general use and a sum of five million dollars
has been paid by the Carnegie Corporation of New York as an increase to
the Endowment Fund of the Institution, payments having been completed in
1931. The Institution was originally organized under the laws of the Dis-
trict of Columbia and incorporated as the Carnegie Institution, articles of
incorporation having been executed on January 4, 1902. The Institution
was reincorporated, however, by an act of the Congress of the United
States, approved April 28, 1904, under the title of The Carnegie Institution
of Washington. (See existing Articles of Incorporation on following pages.)

Organization under the new Articles of Incorporation was effected May
18, 1904, and the Institution was placed under the control of a board of
twenty-four trustees, all of whom had been members of the original corpora-
tion. The trustees meet annually in December to consider the affairs of
the Institution in general, the progress of work already undertaken, the
initiation of new projects, and to make the necessary appropriations for the
ensuing year. During the. intervals between the meetings of the trustees
the affairs of the Institution are conducted by an Executive Committee
chosen by and from the Board of Trustees and acting through the President
of the Institution as chief executive officer.

The Articles of Incorporation of the Institution declare in general "that
the objects of the corporation shall be to encourage, in the broadest and most
liberal manner, investigation, research, and discovery, and the application
of knowledge to the improvement of mankind."

The Institution is essentially an operating organization. It attempts to
advance fundamental research in fields not normally covered by the activi-
ties of other agencies, and to concentrate its attention upon specific problems,
with the idea of shifting attack from time to time to meet the more pressing
needs of research as they develop with increase of knowledge. Some of these
problems require the collaboration of several investigators, special equipment,
and continuous effort. Many close relations exist among activities of the
Institution, and a divisional type of organization, representing investigations
in plant biology, in animal biology, and in historical research, has been
effected in order to make possible a larger degree of unity and closer coopera-
tion. An advisory committee representing the interests of the Institution in
the physical sciences facilitates research in that field. Conference groups on
various subjects have played a part in bringing new vision and new methods
to bear upon many problems. Constant efforts are made to facilitate inter-
pretation and application of results of research activities of the Institution,
and an Office of Publications provides means for appropriate publication,
both in the form of technical monographs and as news bulletins.

ARTICLES OF INCORPORATION

Public No. 260. — An Act To incorporate the Carnegie Institution of

Washington

Be it enacted by the Senate and House of Representatives of the United
States of America in Congress assembled, That the persons following being
persons who are now trustees of the Carnegie Institution, namely, Alexander
Agassiz, John S. Billings, John L. Cadwalader, Cleveland H. Dodge, William
N. Frew, Lyman J. Gage, Daniel C. Gilman, John Hay, Henry L. Higginson,
William Wirt Howe, Charles L. Hutchinson, Samuel P. Langley, William
Lindsay, Seth Low, Wayne MacVeagh, Darius 0. Mills, S. Weir Mitchell,
William W. Morrow, Ethan A. Hitchcock, Elihu Root, John C. Spooner,
Andrew D. White, Charles D. Walcott, Carroll D. Wright, their associates
and successors, duly chosen, are hereby incorporated and declared to be a
body corporate by the name of the Carnegie Institution of Washington and
by that name shall be known and have perpetual succession, with the
powers, limitations, and restrictions herein contained.

Sec, 2. That the objects of the corporation shall be to encourage, in the
broadest and most liberal manner, investigation, research, and discovery,
and the application of knowledge to the improvement of mankind; and in
particular —

(a) To conduct, endow, and assist investigation in any department of
science, literature, or art, and to this end to cooperate with governments,
universities, colleges, technical schools, learned societies, and individuals.

(b) To appoint committees of experts to direct special lines of research.

(d) To conduct lectures, hold meetings and acquire and maintain a
library.

(e) To purchase such property, real or personal, and construct such build-
ing or buildings as may be necessary to carry on the work of the corporation.

(f) In general, to do and perform all things necessary to promote the
objects of the institution, with full power, however, to the trustees herein-
after appointed and their successors from time to time to modify the con-
ditions and regulations under which the work shall be carried on, so as to
secure the application of the funds in the manner best adapted to the con-
ditions of the time, provided that the objects of the corporation shall at all
times be among the foregoing or kindred thereto.

Sec. 3. That the direction and management of the affairs of the corpora-
tion and the control and disposal of its property and funds shall be vested
in a board of trustees, twenty-two in number, to be composed of the follow-
ing individuals: Alexander Agassiz, John S. Billings, John L. Cadwalader,
Cleveland H. Dodge, William N. Frew, Lyman J. Gage, Daniel C. Gilman,
John Hay, Henry L. Higginson, William Wirt Howe, Charles L. Hutchin-
son, Samuel P. Langley, William Lindsay, Seth Low, Wayne MacVeagh,

Xll

ARTICLES OF INCORPORATION

Darius 0. Mills, S. Weir Mitchell, William W. Morrow, Ethan A. Hitch-
cock, Elihu Root, John C. Spooner, Andrew D. White, Charles D. Walcott,
Carroll D. Wright, who shall constitute the first board of trustees. The
board of trustees shall have power from time to time to increase its mem-
bership to not more than twenty-seven members. Vacancies occasioned by
death, resignation, or otherwise shall be filled by the remaining trustees in
such manner as the by-laws shall prescribe ; and the persons so elected shall
thereupon become trustees and also members of the said corporation. The
principal place of business of the said corporation shall be the city of
Washington, in the District of Columbia.

Sec. 4. That such board of trustees shall be entitled to take, hold, and
administer the securities, funds, and property so transferred by said Andrew
Carnegie to the trustees of the Carnegie Institution and such other funds
or property as may at any time be given, devised, or bequeathed to them,
or to such corporation, for the purposes of the trust; and with full power
from time to time to adopt a common seal, to appoint such officers, members
of the board of trustees or otherwise, and such employees as may be deemed
necessary in carrying on the business of the corporation, at such salaries or
with such remuneration as they may deem proper; and with full power to
adopt by-laws from time to time and such rules or regulations as may be
necessary to secure the safe and convenient transaction of the business of
the corporation; and with full power and discretion to deal with and expend
the income of the corporation in such manner as in their judgment will best
promote the objects herein set forth and in general to have and use all
powers and authority necessary to promote such objects and carry out
the purposes of the donor. The said trustees shall have further power from
time to time to hold as investments the securities hereinabove referred to
so transferred by Andrew Carnegie, and any property which has been or
may be transferred to them or such corporation by Andrew Carnegie or by
any other person, persons, or corporation, and to invest any sums or
amounts from time to time in such securities and in such form and manner
as are permitted to trustees or to charitable or literary corporations for
investment, according to the laws of the States of New York, Pennsylvania,
or Massachusetts, or in such securities as are authorized for investment by
the said deed of trust so executed by Andrew Carnegie, or by any deed of
gift or last will and testament to be hereafter made or executed.

Sec. 5. That the said corporation may take and hold any additional
donations, grants, devises, or bequests which may be made in further sup-
port of the purposes of the said corporation, and may include in the ex-
penses thereof the personal expenses which the trustees may incur in
attending meetings or otherwise in carrying out the business of the trust,
but the services of the trustees as such shall be gratuitous.

Sec. 6. That as soon as may be possible after the passage of this Act a
meeting of the trustees hereinbefore named shall be called by Daniel C.
Gilman, John S. Billings, Charles D. Walcott, S. Weir Mitchell, John Hay,
Elihu Root, and Carroll D. Wright, or any four of them, at the city of
Washington, in the District of Columbia, by notice served in person or by
mail addressed to each trustee at his place of residence; and the said

xiii

ARTICLES OF INCORPORATION

trustees, or a majority thereof, being assembled, shall organize and proceed
to adopt by-laws, to elect officers and appoint committees, and generally to
organize the said corporation; and said trustees herein named, on behalf
of the corporation hereby incorporated, shall thereupon receive, take over,
and enter into possession, custody, and management of all property, real
or personal, of the corporation heretofore known as the Carnegie Institu-
tion, incorporated, as hereinbefore set forth under "An Act to establish a
Code of Law for the District of Columbia, January fourth, nineteen hun-
dred and two," and to all its rights, contracts, claims, and property of any
kind or nature; and the several officers of such corporation, or any other
person having charge of any of the securities, funds, real or personal, books
or property thereof, shall, on demand, deliver the same to the said trustees
appointed by this Act or to the persons appointed by them to receive the
same; and the trustees of the existing corporation and the trustees herein
named shall and may take such other steps as shall be necessary to carry
out the purposes of this Act.

Sec. 7. That the rights of the creditors of the said existing corporation
known as the Carnegie Institution shall not in any manner be impaired by
the passage of this Act, or the transfer of the property hereinbefore men-
tioned, nor shall any liability or obligation for the payment of any sums
due or to become due, or any claim or demand, in any manner or for any
cause existing against the said existing corporation, be released or impaired;
but such corporation hereby incorporated is declared to succeed to the obli-
gations and liabilities and to be held liable to pay and discharge all of the
debts, liabilities, and contracts of the said corporation so existing to the
same effect as if such new corporation had itself incurred the obligation or
liability to pay such debt or damages, and no such action or proceeding
before any court or tribunal shall be deemed to have abated or been dis-
continued by reason of the passage of this Act.

Sec. 8. That Congress may from time to time alter, repeal, or modify this
Act of incorporation, but no contract or individual right made or acquired
shall thereby be divested or impaired.

Sec. 9. That this Act shall take effect immediately.

Approved, April 28, 1904

XIV

BY-LAWS OF THE INSTITUTION

Adopted December 13, 1904. Amended December 13, 1910, December 13, 1912, and

December 10, 1937

Article I

THE TRUSTEES

1. The Board of Trustees shall consist of twenty-four members, with
power to increase its membership to not more than twenty-seven members.
The Trustees shall hold office continuously and not for a stated term.

2. In case any Trustee shall fail to attend three successive annual meet-
ings of the Board he shall thereupon cease to be a Trustee.

3. No Trustee shall receive any compensation for his services as such.

4. All vacancies in the Board of Trustees shall be filled by the Trustees
by ballot. Sixty days prior to an annual or a special meeting of the Board,
the President shall notify the Trustees by mail of the vacancies to be filled
and each Trustee may submit nominations for such vacancies. A list of the
persons so nominated, with the names of the proposers, shall be mailed to
the Trustees thirty days before the meeting, and no other nominations shall
be received at the meeting except with the unanimous consent of the Trus-
tees present. Vacancies shall be filled from the persons thus nominated, but
no person shall be declared elected unless he receives the votes of two-thirds
of the Trustees present.

Article II

MEETINGS

1. The annual meeting of the Board of Trustees shall be held in the City
of Washington, in the District of Columbia, on the first Friday following
the second Thursday of December in each year.

2. Special meetings of the Board may be called by the Executive Com-
mittee by notice served personally upon, or mailed to the usual address of,
each Trustee twenty days prior to the meeting.

3. Special meetings shall, moreover, be called in the same manner by the
Chairman upon the written request of seven members of the Board.

Article III

OFFICERS OF THE BOARD

1. The officers of the Board shall be a Chairman of the Board, a Vice-
Chairman, and a Secretary, who shall be elected by the Trustees, from the
members of the Board, by ballot to serve for a term of three years. All
vacancies shall be filled by the Board for the unexpired term; provided,
however, that the Executive Committee shall have power to fill a vacancy
in the office of Secretary to serve until the next meeting of the Board of
Trustees.

BY-LAWS OF THE INSTITUTION

2. The Chairman shall preside at all meetings and shall have the usual
powers of a presiding officer.

3. The Vice-Chairman, in the absence or disability of the Chairman, shall
perform his duties.

4. The Secretary shall issue notices of meetings of the Board, record its
transactions, and conduct that part of the correspondence relating to the
Board and to his duties. He shall execute all deeds, contracts or other
instruments on behalf of the corporation, when duly authorized.

Article IV

EXECUTIVE ADMINISTRATION

The President

1. There shall be a President who shall be elected by ballot by, and hold
office during the pleasure of, the Board, who shall be the chief executive
officer of the Institution. The President, subject to the control of the Board
and the Executive Committee, shall have general charge of all matters of
administration and supervision of all arrangements for research and other
work undertaken by the Institution or with its funds. He shall devote his
entire time to the affairs of the Institution. He shall prepare and submit to
the Board of Trustees and to the Executive Committee plans and sug-
gestions for the work of the Institution, shall conduct its general corre-
spondence and the correspondence with applicants for grants and with the
special advisers of the Committee, and shall present his recommendations
in each case to the Executive Committee for decision. All proposals and
requests for grants shall be referred to the President for consideration and
report. He shall have power to remove and appoint subordinate employees
and shall be ex officio a member of the Executive Committee.

2. He shall be the legal custodian of the seal and of all property of the
Institution whose custody is not otherwise provided for. He shall affix the
seal of the corporation whenever authorized to do so by the Board of Trus-
tees or by the Executive Committee or by the Finance Committee. He
shall be responsible for the expenditure and disbursement of all funds of the
Institution in accordance with the directions of the Board and of the
Executive Committee, and shall keep accurate accounts of all receipts and
disbursements. He shall submit to the Board of Trustees at least one
month before its annual meeting in December a written report of the opera-
tions and business of the Institution for the preceding fiscal year with his
recommendations for work and appropriations for the succeeding fiscal
year, which shall be forthwith transmitted to each member of the Board.

3. He shall attend all meetings of the Board of Trustees.

Article V

COMMITTEES

1. There shall be the following standing Committees, viz. an Executive
Committee, a Finance Committee, and an Auditing Committee.

2. The Executive Committee shall consist of the Chairman and Secre-
tary of the Board of Trustees and the President of the Institution ex officio

xvi

BY-LAWS OF THE INSTITUTION

and, in addition, five trustees to be elected by the Board by ballot for a
term of three years, who shall be eligible for re-election. Any member
elected to fill a vacancy shall serve for the remainder of his predecessor's
term: Provided, however, that of the Executive Committee first elected
after the adoption of these by-laws two shall serve for one year, two shall
serve for two years, and one shall serve for three years; and such Com-
mittee shall determine their respective terms by lot.

3. The Executive Committee shall, when the Board is not in session and
has not given specific directions, have general control of the administration
of the affairs of the Corporation and general supervision of all arrangements
for administration, research, and other matters undertaken or promoted by
the Institution; shall appoint advisory committees for specific duties; shall
determine all payments and salaries; and keep a written record of all trans-
actions and expenditures and submit the same to the Board of Trustees at
each meeting, and it shall also submit to the Board of Trustees a printed
or typewritten report of each of its meetings, and at the annual meeting
shall submit to the Board a report for publication.

4. The Executive Committee shall have general charge and control of all
appropriations made by the Board.

5. The Finance Committee shall consist of five members to be elected
by the Board of Trustees by ballot for a term of three years.

6. The Finance Committee shall have custody of the securities of the
corporation and general charge of its investments and invested funds, and
shall care for and dispose of the same subject to the directions of the Board
of Trustees. It shall consider and recommend to the Board from time to
time such measures as in its opinion will promote the financial interests of
the Institution, and shall make a report at each meeting of the Board.

7. The Auditing Committee shall consist of three members to be elected
by the Board of Trustees by ballot for a term of three years.

8. The Auditing Committee shall, before each annual meeting of the
Board of Trustees, examine the accounts of business transacted under the
Finance Committee and the Executive Committee. They may avail them-
selves at will of the services and examination of the Auditor appointed by
the Board of Trustees. They shall report to the Board upon the collection
of moneys to which the Institution is entitled, upon the investment and
reinvestment of principal, upon the conformity of expenditures to appro-
priations, and upon the system of bookkeeping, the sufficiency of the
accounts, and the safety and economy of the business methods and safe-
guards employed.

9. All vacancies occurring in the Executive Committee and the Finance
Committee shall be filled by the Trustees at the next regular meeting. In
case of vacancy in the Finance Committee or the Auditing Committee, upon
request of the remaining members of such committee, the Executive Com-
mittee may fill such vacancy by appointment until the next meeting of the
Board of Trustees.

10. The terms of all officers and of all members of committees shall con-
tinue until their successors are elected or appointed.

XVll

BY-LAWS OF THE INSTITUTION
Article VI

FINANCIAL ADMINISTRATION

1. No expenditure shall be authorized or made except in pursuance of a
previous appropriation by the Board of Trustees.

2. The fiscal year of the Institution shall commence on the first day of
November in each year.

3. The Executive Committee, at least one month prior to the annual
meeting in each year, shall cause the accounts of the Institution to be
audited by a skilled accountant, to be appointed by the Board of Trustees,
and shall submit to the annual meeting of the Board a full statement of the
finances and work of the Institution and a detailed estimate of the expendi-
tures of the succeeding year.

4. The Board of Trustees, at the annual meeting in each year, shall make
general appropriations for the ensuing fiscal year; but nothing contained
herein shall prevent the Board of Trustees from making special appropria-
tions at any meeting.

5. The securities of the Institution and evidences of property, and funds
invested and to be invested, shall be deposited in such safe depository or in
the custody of such trust company and under such safeguards as the Trus-
tees and Finance Committee shall designate; and the income available for
expenditure of the Institution shall be deposited in such banks or deposi-
tories as may from time to time be designated by the Executive Committee.

6. Any trust company entrusted with the custody of securities by the
Finance Committee may, by resolution of the Board of Trustees, be made
Fiscal Agent of the Institution, upon an agreed compensation, for the trans-
action of the business coming within the authority of the Finance Committee.

Article VII

AMENDMENT OF BY-LAWS

1. These by-laws may be amended at any annual or special meeting of
the Board of Trustees by a two-thirds vote of the members present, pro-
vided written notice of the proposed amendment shall have been served
personally upon, or mailed to the usual address of, each member of the
Board twenty days prior to the meeting.

XV 111

ABSTRACT OF MINUTES OF THE THIRTY-NINTH
MEETING OF THE BOARD OF TRUSTEES

Upon call of the Executive Committee, and in accordance with instructions
of the Board of Trustees at its annual meeting of December 10, 1937, a special
meeting of the Board was held in New York City in the offices of the Carnegie
Corporation of New York, 522 Fifth Avenue, on Thursday, June 2, 1938.
The meeting was called to order at 2:30 p.m. by the Chairman, Mr. Forbes.

Upon roll-call, the following Trustees responded: Thomas Barbour, James
F. Bell, Robert Woods Bliss, Frederic A. Delano, Homer L. Ferguson,
W. Cameron Forbes, Walter S. Gifford, Herbert Hoover, Frank B. Jewett,
Stewart Paton, Elihu Root, Jr., Henry R. Shepley, William Benson Storey,
Richard P. Strong, James W. Wadsworth, Frederic C. Walcott, and Lewis
H. Weed.

The Chairman reviewed the action of the Board of Trustees taken at its.
annual meeting on December 10, 1937, calling attention to the election of
Dr. John C. Merriam as President Emeritus of the Institution beginning
January 1, 1939, and to necessity for selection of a new president.

Mr. Walcott, chairman of the special committee appointed to select a can-
didate for the presidency, reported that after careful consideration of numer-
ous candidates the committee on nomination had agreed upon the name of
Dr. Vannevar Bush, of Massachusetts Institute of Technology, and that Dr.
Bush had given consent to have his name presented and had expressed his
willingness to accept if elected. Mr. Walcott stated that the nomination
of Dr. Bush had also been discussed at the meeting of the Executive Com-
mittee immediately preceding the present meeting of the Board with the
result that the Executive Committee had voted to recommend favorable
action by the Board upon Dr. Bush's nomination.

The Board then proceeded to consider the recommendations of the com-
mittee on nomination and of the Executive Committee that Dr. Bush be
elected to the presidency. After discussion, as no other nomination than
that of Dr. Bush had been offered, the Board proceeded to ballot upon his
nomination. It was found that seventeen votes had been cast, all for Dr.
Bush, and he was declared unanimously elected to the presidency of the
Carnegie Institution of Washington, effective January 1, 1939.

Upon motion of Mr. Hoover, the Executive Committee was asked to pre-
pare expression of the genuine sentiment of the Board with regard to the
wide extent and high character of the services of the retiring President,
Dr. Merriam.

Upon motion of Mr. Shepley, a vote of appreciation was authorized in
recognition of the time and service rendered by the members of the nominat-
ing committee, consisting of Mr. Walcott, chairman, Mr. Bell, and Dr. Jewett.

The meeting adjourned at 3:10 p.m.

XIX

ABSTRACT OF MINUTES OF THE FORTIETH
MEETING OF THE BOARD OF TRUSTEES

The meeting was held in Washington in the Board Room of the Admin-
istration Building on Friday, December 9, 1938. It was called to order by
the Chairman, Mr. Forbes.

Upon roll call, the following Trustees responded: Thomas Barbour, Robert
Woods Bliss, Frederic A. Delano, Homer L. Ferguson, W. Cameron Forbes,
Herbert Hoover, Frank B. Jewett, Alfred L. Loomis, Roswell Miller, Henry
S. Morgan, Stewart Paton, Elihu Root, Jr., Henry R. Shepley, William
Benson Storey, Richard P. Strong, Charles P. Taft, James W. Wadsworth,
Frederic C. Walcott, and Lewis H. Weed. The President of the Institution,
Dr. John C. Merriam, and the President-Elect, Dr. Vannevar Bush, were
also in attendance.

An abstract of the minutes of the thirty-ninth meeting, held in New York
on June 2, 1938, was read by the Secretary, Mr. Delano, and was approved
as printed and distributed to the members of the Board.

Reports of the President, the Executive Committee, the Auditor, the
Finance Committee, the Auditing Committee, and of Chairmen of Divisions,
Directors of Departments, and Research Associates of the Institution were
presented and considered.

The following appropriations for the year 1939 were authorized:

Pension Fund $60,000

Administration 104,440

Publications (including Office of Publications) 67,640

Departments and Divisions of Research 1,083,211

Minor Grants 124,000

General Contingent Fund 60,000

Special Emergency Reserve Fund 20,000

$1,519,291

Balloting for a Trustee to fill a vacancy in the Board, caused by the death
of Dr. Campbell, resulted in the election of Dr. Walter A. Jessup, President
of the Carnegie Foundation for the Advancement of Teaching.

The resignation of Stewart Paton as a member of the Executive Committee
was presented and accepted with regret.

Walter S. Gifford and Frederic C. Walcott were elected to succeed them-
selves for a period of three years as members of the Executive Committee,
and Dr. Walter A. Jessup was elected a member of the Executive Committee
to fill the unexpired term of Dr. Paton.

The following resolution was authorized:

Resolved, That the Trustees approve the creation of four standing committees of
their number to advise with the President concerning the activities of the Institution
in the following fields of research: astronomical, terrestrial, biological, historical.
These committees shall meet from time to time and, in consultation with the Presi-
dent, shall examine into the activities of the Institution in their respective fields.
They shall report their conclusions and recommendations through the Executive
Committee to the Board. The Chairman shall appoint these committees annually.

The report of the President was delivered in person.

The President expressed to the Board his personal appreciation of the
manner in which it had met his suggestion regarding retirement. He spoke
especially of his election as President Emeritus with provision for conduct
of his researches, and indicated the importance to him of opportunity for
conducting his investigations as President Emeritus in relation to the Insti-
tution. He stated that his researches will be taken up again where he has
been standing for a long time; that is, with the earlier history of things. He
expressed his belief in palaeontology as a good foundation on which to build
a thinking program, because it begins with questions that touch the eternal
verities; and his hope that he may continue to build on this foundation in
many directions.

After expressing appreciation of the publications presented to him on occa-
sion of his retirement, the President referred to a series of papers in this collec-
tion on the relation of research to education and on the position of the
educational institution, the relation of research to the industries, and, later,
the relation of the research institution to education, these articles cover-
ing a period of over forty years. As result of such study he had no doubt
that, so far as the development of fundamental research is concerned, the
situation existing in the Carnegie Institution represents the most favorable
group of conditions in the world for the advancement of research broadly,
and also specifically, provided the various problems are kept in proper rela-
tion to one another and emphasis is maintained on the more fundamental
aspects of research rather than on the specific applications of investigation.

Reference was made to development of the Institution into groups of
agencies, or departments, separated from one another and isolated from the
central administration, and the resulting problem of how so to modify the
relations as to further these activities in such manner as to permit future
flexibility in direction and emphasis of the program as a whole. The effort
to have the Institution concern itself with projects, with specific great objec-
tives which might serve as terminal points for certain investigations, has
developed and serves to prevent freezing up of money, apparatus, and per-
sonnel, and, on the other hand, offers that degree of freedom and mobility
which permits the closing out of some things and concentration of attention
in other directions.

In contrast to institutionalization through isolation of departments, it
was pointed out that there is danger of swinging too far in the other direction
by diffusion of small sums widely without adequate guidance, so that, while
the money is vouchered properly, there may be small yield in scientific result.

For many years, the President stated, the Institution has been sailing
between the Scylla of institutionalization and the Charybdis of the isolated
small grant without relation to the departments. He considers it probable
that such a situation cannot be avoided; that both types of support must
be given; and that there will always be dangers in both.

With reference to the relation between the distinctly research aspect of
the Institution's program, in the sense of experimentation and observation,
and the interpretative aspect, it was recalled that one of the first results
from early exhibitions of the Institution was discovery by some investi-
gators that they could not explain their materials to the visitors easily, and

XXI

that this situation, strangely enough, seemed due to lack of clearly organized
knowledge of the subjects represented. Further study, however, developed
a power of exposition and of interpretation which goes back into the in-
vestigation, sometimes by way of interpretation to the scientific public. It
was brought out that this problem of interpretation has concerned several
things: one is the lay public, and another is the influence upon the investi-
gator. When the Institution initiated its press releases some years ago, it was
assumed that they would be interpreting science to the layman, but it was sur-
prising to find that the first reaction came from workers in other scientific
fields. It was discovered that research was being interpreted to men in other
subjects, which opened a new field, and a new need for interpretation, so that,
as time passed, the interpretational aspect of the Institution's program be-
came increasingly important. Some years ago the period of lag between ob-
taining knowledge and its application was figured at about fifty years ; more
recent calculations place this lag between twenty-five and thirty years, partly
as result of better methods of interpretation.

Reference was made to groups within the Institution studying various
kinds of application, but not with the expectation that they will themselves
apply the results. The studies have been made with a view to finding ways
in which the results could be conveyed to those who are expert in applica-
tion, making the proper contacts so that the flow of knowledge from research
will go easily and quickly to the places where it can be used by those who
know, and so that there will be developed a relation between this kind of
institution and those agencies controlled by engineers or doctors, or whoever
they may be, who are experts in application, so that values are not lost.

Emphasis was laid upon the point that unless there is an enthusiastic
group of persons interested in advancing knowledge by the most funda-
mental research, by the most careful means and the most accurate methods,
unless we are standing upon the truth, everything done is useless. If one does
not depend fully upon securing the truth and using the best methods, then
his assumed facts, his scientific papers, his interpretation through lectures
and exhibits will have little value.

The President expressed his belief that the staff of the Institution at the
present time is good. The leading men on the staff now have in many in-
stances grown up in the Institution, and it is a splendid thing to build up
young men so that they acquire a reputation for their work.

The President declared further that the considerable experience with the
Institution which it has been his privilege to have, at the same time fol-
lowing contact with other kinds of agencies and study of still others, has left a
clear impression that there is no type of institution which offers greater
possibilities for the advance of knowledge through research than the Car-
negie Institution, provided always that it holds to the high ideals set up
at the beginning and that have been maintained by guidance of the Board
of Trustees through these years. Research, in the last analysis, he observed,
seems one of the most important things that the world has thought out. It
gives us so much that the end cannot yet be seen. The limits of the human
mind are not known, but it will be long before men reach a place where re-
search will not be able to produce still more information. The opinion was ex-

XXll

pressed that, with careful guidance, this institution will continue to pay large
dividends, not merely for decades but for centuries to come.

The Chairman called attention to the action of the Board of Trustees at
its special meeting of June 2, 1938, whereby the Executive Committee was
asked to prepare expression of genuine sentiment of the Board with regard
to the wide extent and high character of the services of the retiring President.
The Chairman stated that the foreword to the four volumes of the collected
works of Dr. Merriam which have been printed and presented to him express
such a tribute. President Merriam commented that there could be no finer
tribute than the foreword to these volumes.

The meeting adjourned at 12:35 p. m.

XXI 11

REPORT OF THE EXECUTIVE COMMITTEE

For the Year Ending October 31, 1938

To the Trustees of the Carnegie Institution of Washington:

Gentlemen: Article V, Section 3, of the By-Laws provides that the
Executive Committee shall submit, at the annual meeting of the Board of
Trustees, a report for publication; and Article VI, Section 3, provides that
the Executive Committee shall also submit, at the same time, a full state-
ment of the finances and work of the Institution and a detailed estimate
of the expenditures for the succeeding year. In accordance with these pro-
visions, the Executive Committee herewith respectfully submits its report
for the fiscal year ending October 31, 1938.

During this year the Executive Committee held seven meetings, printed
reports of which have been mailed to each Trustee.

A full statement of the work of the Institution is contained in the report
of the President, which has been considered and approved by the Executive
Committee, and is submitted herewith. A detailed estimate of expenditures
for the succeeding year is also contained in the report of the President, and
has been considered by the Executive Committee, which has approved the
recommendations of the President in respect thereto and has provisionally
approved the budget estimates based thereon and submitted therewith.
The recommendations of the President in this connection were made after
consultation by him on the questions involved with Dr. Vannevar Bush,
President-elect of the Institution. Close attention has been given both by the
Executive Committee and by the Finance Committee to the question of avail-
ability of funds for Institution activities in 1939, and budget recommenda-
tions are based upon judgment of these Committees with respect to financial
policy for protection both of capital and of income, and concerning the prob-
lem of investment of funds.

The Board of Trustees, at its meeting of December 10, 1937, appointed
Arthur Young and Company to audit the accounts of the Institution for the
fiscal year ending October 31, 1938. The report of the Auditor, including a
balance sheet showing assets and liabilities of the Institution on October 31,
1938, is submitted as a part of the report of the Executive Committee.

In addition to the report of the Auditor there is also submitted a financial
statement for the fiscal year ending October 31, 1938, showing funds avail-
able for expenditure and amounts allotted by the Executive Committee, and
a customary statement of receipts and disbursements since the organization
of the Institution on January 28, 1902. These statements together with the
tables in the Auditor's report comprise a full statement of the finances of
the Institution.

Construction of the addition to the Administration Building, which is to
be used primarily for advancing the public relations program of the Institu-
tion, progressed during the past year to a stage at which it was possible to
occupy office space in the structure in October, and it is expected that all

xxiv

details will be completed in advance of initiation of the fall and winter
lecture series.

One vacancy exists in the membership of the Board of Trustees, caused
by the death of W. W. Campbell on June 14, 1938. Nominations to fill
vacancies have been requested, received, and distributed in accordance with
provisions of the By-Laws, and such nominations will be submitted to the
Board at its annual meeting on December 9, 1938.

No vacancies exist among the officers of the Board or in its Committees.
Tenures of office of Messrs. Gifford and Walcott as members of the Execu-
tive Committee expire at the annual meeting on December 9.

W. Cameron Forbes, Chairman
Robert Woods Bliss
Frederic A. Delano
Walter S. Gifford
John C. Merriam
Stewart Paton
Frederic C. Walcott
Lewis H. Weed

November 19, 1938

Financial Statement for Fiscal Year Ending October 31, 1038

Large Grants:
Animal Biology:

Administrative Expenses.

Embryology

Genetics

Nutrition Laboratory . . . .
Tortugas Laboratory
Geophysical Laboratory . . .

Historical Research

Mount Wilson Observatory.

Plant Biology

Terrestrial Magnetism

Minor Grants

Publications

Administration

Pension Fund

General Contingent Fund . . . .
Special Emergency Reserve
Fund *

Balances

unallotted

Oct. 31,

1937

$5,297.06
55,740.97

46,028.69

107,066.72

Trustees'
appropri-
ation Dec.
10, 1937

$2,300

78,642

144,645

30,000

14,000

156,282

152,890

219,530

96,479

189,310

115,500

97,220

64,550

60,000

110,000

130,000

1,661,348

Revert-
ments and
transfers
Nov. 1,
1937, to
Oct. 31,
1938

$1,700

1,100
500

1,500

6,825

4,800
27,150

9,025

6,829.22
33,068.95
12,454.74
15,700

34 , 840 . 64

155,493.55

Total

available

1938

$2,300

80.342
145,745

30,500

15,500
163,107
157,690
246,680
105,504
196,139.22
153,866.01
165,415.71

80 , 250

60,000
190,869.33

130,000

1,923,908.27

Executive

Committee

allottments

1938

$2,300

80,342
145,745

30,180

15,500
163,107
157,690
246,680
105,504
196,139.22
144,000.00
104,195.09

80,250

60,000

47,226.28

130,000

1,708,858.59

Transfers
by Execu-
tive Com-
mittee

$76,129.22

76,129.22

Unallotted

balances

Oct. 31,

1938

$320

9,866.01
61,220.62

67,513.83

138,920.46

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XXVI

REPORT OF AUDITORS

To the Board of Trustees

Carnegie Institution of Washington
Washington, D. C.

We have made an examination of the books and accounts of Carnegie
Institution of Washington for the year ended October 31, 1938.

Income from investments and other sources has been duly accounted for
and all disbursements were evidenced by paid voucher checks and/or
properly approved invoices. The cash and securities were either verified
by inspection or by certificates received from depositaries and custodians.
As in the past years, the detail accounts of the Departments of Research
in the field have been audited by the Bursar of the Institution and we are
of the opinion, as a result of reviewing the internal audit methods in force,
that such internal audit is satisfactorily conducted.

The securities are stated at cost or value at date acquired, this being
the established custom of the Institution. Real estate and equipment are
stated at original cost and books on hand for sale at their sales prices.

We inspected certified copies of the minutes of the meetings of the
Board of Trustees and Executive Committee as authority for the appro-
priations and allotments made during the year.

In our opinion, on the basis of valuations stated above, the accom-
panying Balance Sheet, statement of Receipts and Disbursements and de-
tailed Schedule of Securities properly present the financial position of the
Carnegie Institution of Washington at October 31, 1938 and the trans-
actions for the year ended that date.

Arthur Young & Company

Accountants and Auditors

New York, N. Y., November 28, 1938

XXVll

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XXIX

Schedule of Securities

Aggregate —

Description

Registered

Ma-
turity

Int.
Due

Total Cost or

Par or

Nominal

Value

Princ.
Int.

Princ.
Only

Value at Date
Acquired

$500 000

Railways
A. T. & S. Fe 1st & ref. 4}^s

1962
1955
1995
1941
1948
1995
1996
1961
1967
1969
1957
1954
1962
1992
1939-40
1949
1949
1958
1949
1975
1966
2000

1989
1987
1987
1952
1963
1952
1939

1977
1993
1941
1996

1942-43
1961
1977
1973
1963
1955

1942-44
1960

1936
1957
1954
1949
2003
1990
1977
1939-42

1977
2013
2013

1978
1950
1946
2047
2047
1946

1961
1965
1960
1956
1975
1952
1955
1969
1994
1950

1939
1953
1977

1960
1946
2008
1966
1939
1976
2361
1977

M-S
J-D
A-0
M-N
JAJO
J-D
M-S
A-0
M-S

J-J

J-D

A-0

M-S

M-N

F-A

J-J
M-S

J-J
F-A
M-N
A-O

J-J
FMAN

M-N
M-S
J-J
J-J
J-J

J-J
J-D
M-N
J-J
J-D
J-J
J-J
J-J
J-D
M-N
A-O
J-J

A-0
M-S

F-A

M-S
A-0
J-D

M-S
M-N

M-S
A-0
A-O

M-S
M-S

J-J

J-J
FMAN

J-J

J-J
J-D
F-A
J-J
A-0

J-J

M-N
J-J
J-J

A-0
J-J
A-0

J-D
J-D

M-S
M-S
M-N
F-A

J-J

$498 750.

000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000

000
000
000
000
000
000
000

000
000
000
000
000
000
000
000
000
000
000
000

000
000
000
000
000
000
000
000

000
000
000

000
000
000
000
000
000

000
000
000
000
,000
,000
,000
,000
,000
000

000
000
000

,000
000
,000
,000
000
000
000

A. T. & S. Fe Conv. 4s

105

102

151

112

159

174

169

189

127

227
100
210
280

52
140

107

242

114

180

311

108

115

134

187
229
104

48
249

82
212
192

145

87
2

51
52
49
150
33
49

274

130

311

116

180

362

203

30
147
213

2,084

128

153

37
203

78
170

022 . 50

A. T. & S. Fe gen. 4s

056.25

Balto. & Ohio R. R. ref. 4s

875.

100

Balto. & Ohio R. R. 1st Mtg. 5s

*
*

500.

100
50

Balto. & Ohio R. R. gen. and ref. 5s

416.67
307 . 50

Boston & Maine R. R. Co. 1st Mtg. 4%s. .

163.22

176

137.64

100

Canadian National Ry. Co. 5s

500.

100

000.

160

710.07

021.50

175

062 . 50

100

Ches. & Ohio Ry. Eq. Tr., Series 1929 43^s.
Central Pac. Ry. 1st ref. 4s

825 . 50

250.

100

Chicago, B. & Q. R. R. 111. Div. 3^s

099 . 87

180

Chicago B. & Q. R. R. gen. 4s

*
*

501.25

100
35

Chicago B. & Q. R. R. 111. Div. 4s

Chicago M. St. P. & P. 5s

750.
853.50

189

Chicago Ind. & L. 1st & gen. 5s

461.25

140

Chicago M. St. P. & P. conv. adj. 5s

414.50

234

Chicago M. & St. P. Ry. gen. 4^s ($5,000
fully reg., $29,000 reg. princ.)

*
*

162.50

120

Chicago & N. W. Ry. gen. 3J/£s

300.

200

000.

300

Chicago, R. I. & P. Ry. 43^s

964 . 50

Chicago Union Station Co., 1st Mtg. 3%s.

125.

150

Chicago & W. Indiana R. R. Co., cons. 4s.

715.27

Clev. C. C. & St. Louis Ry., 1st 4s

500.

100

Clev. C. C. & St. Louis Ry., ref. and imp.
4^s

272 . 50

100

Clev. C. C. & St. Louis Ry. gen. 4s

906.25

100

Elgin, Joliet & E. Ry. Co., 5s

125.

300

Erie R. R. gen. 4s

937.50

Erie R. R. Eq. Trust 4^s

467.90

69
117

Great Northern Ry. gen. 4J^s

053.25
806.25

173

Great Northern Ry. gen. 5s

587.50

300

111. Cent. R. R. Joint 5s

291.50

121

111. Cent. R. R. ref. 4s

677.50

120

111. Cent. Eq. Trust 4J^s

184.84

150

Kan. City Term. 1st 4s

796.57

200

Kan. City, F. S. & M. Ry. ref. 4s (Certifi-
cate of Deposit)

250.

225

Lehigh and L. E. 43^s

547.29

100

Lehigh V. H. Term. Ry. 1st 5s

750.

Long Island ref. 4s

285.

250

Louisville & N. R. R. 1st & ref. 4J^s

125.

100

Mo. Kan. & T. 1st 4s

603.13

213

762 . 50

200

Mo. Pac. R. R., Eq. Trust 4^s

206 . 79

150

Mobile and O. R. R. ref. and imp. 43>-£s

750.

186

N. Y. Cent. R. R. ref. & imp. 4J^s

663 . 45

N. Y. Cent. R. R. ref. & imp. 5s

556 , 25

New York, Chicago & St. L. R. R. Co., ref.
mtg. 43^s

536.25

New York, Penna. & Ohio R. R. 4^s

500.

N. Y. W. and Boston 1st 4^s

187.50

150

Northern Pacific ref. and imp. 6s

450.

Northern Pacific gen. lien 3s

101.25

Oregon Short Line con. 5s

373.25

310

Oregon Wash. R. & N. 1st ref. 4s. ($50,000
fully registered)

*
*
*

272.50

Penna. R. R. Co. gen. 43^s

900.

125

Penna. R. R. Co. con. 4^s

703.13

282 . 50

300

Pitts. C. C. & St. L. 5s

393.75

Pitts. Shawmut & Nor. 4s (Ctf . Dep.)

200.

125
200

So. Pac. 1st ref. 4s ($100,000 fully reg.) . .
So. Pac. conv. 4j^s

617.50
000.

350

Southern Rwy. Co. 1st con. 5s

531.25

225

St. Louis-S. F., prior lien 4s (Ctf. Dep.) . .

431.25

Term. R. R. Assn. of St. Louis 1st Mtg.,
4^s

400.

162

Term. R. R. Assn. of St. Louis 4s

197 . 60

210

Texas & Pac. Ry., gen. and ref. 5s

882.50

100

Toledo & Ohio Central Ry. Co. ref. &
imp. 3j^s

000.

2,084

Union R. R. deb. 6s

*
*

000.

140

Union Pac. 1st lien and ref. 4s

722 . 50

150

Virginian Ry. Co. 1st Lien & ref. 3%s. . . .

375.

Wabash R. R. Co., 1st 5s

750.

200

Wabash Ry., ref. and gen. 5s

250.

100
200

West Shore R. R. Co., 1st Mtg. 4s

Western Md. R. R. 1st & Ref. Mtg. 5^s. .

140.
708.75

12,729

000

Railway Sub-Total

12,167

958.44

XXX

Schedule of Securities — Continued

Aggregate-
Par or
Nominal
Value

Description

$100,000

212,000

175,000

190,000

125,000

300,000

56,000

100,000

300,000

75,000

300,000

110,000

380,000

300,000

23,900

83,000

158,000

50,000

40,000

100,000

250,000

325,000

200,000

90,000

25,000

200,000

173,000

200,000

300,000

280,000

100.000

150,000

300,000

100,000

50,000

100,000

25,000

52,000

100,000

65,000

300,000

150,000

50,000

100,000

175,000

100,000

200,000

100,000

200,000

300,000

105,000

136,000

141,000

70,000

60,000

50,000

75,000

250,000

75,000
200,000
125,000
300,000
200,000
120,000
250,000

220,000
263,000
235,000

100,000

213,000

Registered

Princ.
Int.

Public Utility

Ala. Power Co. 1st & ref. 4j^s

Ala. Power Co. 1st & ref. 5s

Am. Tel. & Tel. Co. deb. 3Ms

Am. Tel. & Tel. Co. sink. deb. 53^s

Appalachian Electric Power Co.lst Mtg. 4s

Ark. P. & L. Co. 5s

Bell Tel. Co. of Canada 1st 5s

Birmingham Electric Co., 1st ref. 4Ks. . . .

Blackstone Valley Gas & E. 4s

Carolina Power & L. Co. 1st & ref. 5s

Cedar R. Mfg. & P. Co. 1st sink. 5s

Columbia Gas and Elec. Corp., deb. 5s. . .

Columbus Rwy., P. & L. 4s

Commonwealth Edison Co. Conv. 3Ks. . .
Commonwealth Edison Co. 1st Mtg. 3^s.
Commonwealth Edison Co. 1st Mtg. 4s. .
Consolidated Edison Co. of N.Y. deb. 3J^s
Consolidated Edison Co. of N.Y. deb. 3^s

Detroit Edison gen. & ref. 4s

Gatineau Power, 1st 5s

Georgia Power Co. 1st ref. 5s

Gulf States Util. Co. 1st Mtg. & ref. 4s.. .
Hackensack Water Co., Gen. & Ref. 5Hs.
Houston Ltg. & Power Co. 1st mtg. 3^s.

Illinois P. & L., 1st & ref. 5s

Indianapolis P. & L. 1st 3%s

Ind. & Mich. Elec. Corp., 1st ref. 5s

Inter. Tel. & Tel. deb. 4^s

Interborough Rap. Trans, ref. 5s

Iowa Southern Utilities Co. 1st & ref. 53^s.

Louisiana Power & Light Co., 1st 5s

Memphis P. & L. 1st & ref. 4^s

Metropolitan Edison Co. 1st 4^s

Minnesota P. & L. 1st & ref. 4^s

Monongahela West Penn. Pub. Serv. Co.
1st & gen. 4^s

Montana Power Co., 1st & Ref. 3%s

Mountain States Tel. & Tel. Co. Deb. 3Ms

New Eng. Tel. & Tel. 5s

New Orleans Pub. S. 5s

New York & Westchester Ltg. 5s

New York P. & L., 1st 4j^s

Northern Ind. Pub. S., 1st ref. 5s

Northern States Power Co., 1st & Ref. 3}4s

Ohio Edison Co. 1st Mtg. 4s

Ohio Power Co. 1st 3^s

Ohio Power Co., 1st and ref. 4j^s

Ohio Public Serv. Co., 1st Mtg. 4s

Okla. G. & E. 1st 3%s

Oklahoma Natural Gas Co. 1st Mtg. 4Ks.

Pac. G. & E. Co., 1st & ref. 3%s

Pac. G. & E. Co., 1st & ref. 4s

Penn. Electric Co., 1st & Ref. 5s

Penn. Power & L. Co., 1st mtg. 4j^s

Penn. Water & Power Co., 1st ref. 43^s. .

Pub. Serv. Co. of Indiana, 1st & ref. 6s.. .

Pub. Serv. Co. of No. 111., 1st Mtg. 3^s. .

Pub. Serv. Co. of No. 111. 1st Lien & Ref.
4Ms

Puget Sound Power & L. 1st & Ref. 4^s

Puget Sound Power & L. 1st & ref. 53^s.

Rochester Gas & Elec. Corp. gen. 5s. . . .

Shawinigan Water & Power Co., 1st &
coll. 4J^s

Southern Bell Tel. & Tel. Co. Deb. 3^s.

So. Calif. Edison Co., 1st & ref. 3%s

Tenn. E. & P. 1st & ref. 5s

Texas Electric Service 5s

Texas Power & Light Co. 1st & ref. 5s. . .

Toledo Edison 1st Mtg. 3^s

Union Elec. Co. of Missouri, 1st Coll.

Trust 3Ms

Utah L. & T. Co., ref. 5s

Virginia Elec. & Power Co. 1st & ref. 33^s
Washington Water Power Co., 1st & gen.

mtg. 5s

Western United Gas & Electric Co., 1st

Mtg. 5^s

Wisconsin Electric Power Co. 1st 3Hs. .

Princ
Only

Ma-
turity

11,825,900

Public Utility Sub-Total ,

1967
1968
1961
1966
1943
1963
1956
1955
1957
1968
1965
1956
1953
1961
1965
1958
1968
1981
1948
1958
1965
1956
1967
1966
1977
1966
1956
1968
1955
1952
1966
1950
1957
1978
1968
1978

1960
1966
1968
1952
1955
1954
1967
1966
1967
1967
1968
1956
1962
1966
1951
1961
1964
1962
1981
1968
1952
1968

1981
1950
1949
1962

1967
1962
1960
1956
1960
1956
1968

1962
1944
1968

1960

1955

1968

Int.
Due

J-D

M-S
A-O
J-D
M-N
F-A
A-O
M-S
J-D
M-S
M-N
A-O
J-J
J-J
M-N
J-J
J-D
M-S
A-O
J-J
A-O
J-D
M-S
A-O
J-J
J-D
J-D
F-A
M-S
J-J
J-J
M-N
J-D
A-O
M-S
M-N

A-O
J-D
J-D
J-D
J-D
J-J
A-O
M-N
F-A
M-S
A-O
J-D
F-A
J-D
M-N
J-D
J-D
A-O
A-O
M-S
F-A
A-O

A-O
J-D
J-D
M-S

A-O
A-O
J-J
J-D
J-J
M-N
J-J

J-J
A-O

M-S

J-J

J-D
A-O

Total Cost or

Value at Date

Acquired

$87 , 265 .

202,322.50

176,750.

193 , 800 .

130,260.62

296,250.

292,312.50

57,715.
101,125.
283,056.25

76,875.
302,298.75
109,560.50
379,762.50
304 , 500 .

23,910.75

85,712.87
115,465.49

50,875.

40,730.
103,500.
248,958.33
320,112.50
206,000.

97,243.75

25,750.
196,750.
173,000.
202,182.50
288,250.
276,701.
100,474.66
154,900.
279,250.
109,470.

92,156.25

52,000.
101,000.

25 , 500 .

51,748.

99 , 200 .

67,052.50
286,125.
152,887.50

47,500.
100,266.25
101,500.
163,439.06
102,625.
205,000.

99,500.
102,500.
104,000.
203,882.50
289 , 562 . 50
102,597.06
112,540.
145,230.

66,655.
56 , 550 .
31,900.
69,475.

238,510.42
72,375.
197,000.
127,037.50
292 , 700 .
205,143.75
121,800.

249 , 537 . 50
215,193.
272 , 205 .

237,496.87

105,187.50
220,455.

11,680,123.63

XXXI

Schedule of Securities — Continued

Aggregate —

Par or

Nominal

Value

$25,000

100,000
80,000
98,250

100,000
90,000
99,000

100,000

692,250

Description

Mortgages

Empire Title and Guarantee Co., Guar.

1st Mtg., Ctf. No. 1676 5%

Lawyers Mtg. Co. Guaranteed 1st Mtg.

Ctfs., Series 18397 5J^%

Lawyers Title and Guaranty Co., 5^%

Mortgage

Lawyers Title and Guaranty Co., Guar-
anteed 1st Mortgage 4J^%

Lawyers Mtg. Co., Guaranteed 1st Mtg.

N. Y. Title and Mtg. Co. Guaranteed 1st

Mtg. Ctf., 5^%

N. Y. Title and Mtg. Co. Guaranteed 1st

Mtg. 4V2%

Title Guarantee and Trust Co. 1st Mtg.

Ctf. 130057 3% Participating

Mortgages Sub-Total .

Registered

Princ
Int.

Princ

Only

Ma-
turity

1939
1935
1935
1942
1940
1938
1940
1939

Int.
Due

FMAN

J-J

A-0

J-J

MJSD
J-D
J-D
J-D

Total Cost or

Value at Date

Acquired

$25,000.
100,000.

80,000.

97,758.75
100,000.00

90,000.

99,000.
100,000.
691,758.75

25,000

50,000

100,000

50,000

99,000

6,000

200,000

100,000

94,000

250,000

100,000

53,000

100,000
1,925,000
100,000
100,000
85,000
100,000

Industrial

Addressograph-Multigraph Corp .Deb . 5 3^ fc
Allis-Chalmers Mfg. Co., Conv. Deb. 4s. .
American I. G. Chemical Corp., conv. 5Hs

American Radiator Co., Deb. 4Hs

Bethlehem Steel Corp. Cons. sink. fund 4 Ms
Phelps Dodge Corp. Conv. Deb. 3J^s. . . .

Rwy. Express Agency, 5s

Remington Rand, Inc., Deb. 4j^s

Scovill Manufacturing Co., Conv. Deb.

5Ks

Shell Union Oil Corp., Deb. 3Ks

Socony Vacuum Oil Co. Deb. 3^s

Southern Kraft Corp., 1st leasehold &

gen. mtg. 4Ms

Standard Oil Co. of N. J. Deb. 2%s

Tenn. C. I. & R. Co. 5s

Texas Corp., Deb. 3J^s

United States Steel Corp. Deb. 3Ms

Wheeling Steel Corp. 1st Mtg. 4J^s

Youngstown S. & Tube 1st Mtg. sink. 4s. .

1945
1952
1949
1947
1960
1952
1939-48
1956

1945
1951
1950

1946
1953
1951
1951
1948
1966
1961

A-O

M-S
M-N
M-N
J-J
J-D
M-S
M-S

J-J

M-S
A-0

J-D
J-J
J-J
J-D

J-D
F-A

M-N

25,000.

51,587.
105,861.25

49,125.

97,515.
6,000.
200,000.
100,162.50

96,747.66
247,500.
100,000.

51,790.

99,000.

1,925,000.

100,000.

86,275.

98,500.

3,537,000

Industrial Sub-Total.

3,540,063.41

$ 55,000

120,500

40,000

196,000

25,000

75,000

100,000

163,000

100,000

200,000

100,000

40,000

100,000

90,000

50,000

100,000

1,754,500

Foreign

Canada, Dom. of 5s

German External Loan of 1924 7s

Imp. Japanese Govt. 5}4s

Kingdom of Denmark, ext. 43^s. .

City of Montreal 5s

City of Montreal sink. 5s.

City of Montreal 4j^s

New South Wales, ext. 5s

Province of Alberta deb. 4Hs. . . .

Province of Alberta 5s

Province of Manitoba deb. 4J^s. .
Province of Nova Scotia 4J-£s

Province of Ontario 4s

Province of Ontario 6s

City of Toronto con. deb. 5s

City of Toronto, 5s

City of Winnipeg inter, deb. 5s. . .
City of Winnipeg deb. 4^s

Foreign Sub-Total.

1952
1949
1965
1962
1956
1954
1946
1958
1958
1950
1958
1952
1964
1943
1949
1952
1943
1946

M-N

A-O

M-N

A-0

M-N

F-A

A-0

J-J

A-0

M-S

M-N

M-S

J-D

60,450.00
128,738.53
35,900.
179,258.34
24,062.50
72,375.
94,368.90
154,493.44
93,750.
101,150.
190,515.70
100,312.50
87,150.10
43,137.50
96,164.59
89,333.53
48,250.
95 , 375 .

1,694,785.63

50,000

State and Municipal
City of Cleveland, Water Works, 5J^s.. . .

1967
1955
1952
1958
1957

1953-63

1960

M-N
J-D
M-S
F-A

M-N

J-J
J-D

52 , 984 . 60

25,000

City of Detroit, Water Supply, 4s

24,812 50

25,000

City of Detroit, Water Supply, 4^s

25,250.

50 , 000

City of Newark, Street Opening, 5^s. . . .

51,724 94

100 000

City of New York, 43^s

117,062 50

84,000
50,000

State of North Carolina, Highway, 4^s
($30,000 registered)

City and County of San Francisco, Hetch
Hetchy, 5%s

92,819.50
53,523.34

384,000

State and Municipal Sub-Total

418,177.38

30,922,650

Bonds — Funds Invested

30,192,867.24

XXX11

Schedule of Securities — Continued

Number of
Shares

1,100
1,113

700

330
1,500
2,800
1,500
2,600
1,300
1,100
1,300

400

800

708
2,300

900

400

500
1,800
1,800
1,100
1,100

300

600

300

720

420.25
1,300
1,900

413
1,900

900
1,230

400
1,500

900
1,000
1,000
1,200
1,600

500

700
1,000
1,290

800
1,600
2,200
2,000

100

800
1,500
1,000

900

300

600

500
1,520

62,544.25

120

500

2,000

1,000
500
225

1,000
400

5,000

10,812

73,356.25

Description

Common Stocks

Air Reduction Company

Allis-Chalmers Manufacturing Co

Alpha Portland Cement Co

American Brake Shoe and Foundry Co

American Cyanamid Co

American Radiator & Standard Sanitary Corp,

Bethlehem Steel Corp

Borg Warner Corp

Caterpillar Tractor Co

Chrysler Corporation

Commercial Investment Trust Corp

Consolidated Edison Co., of N. Y

Continental Can Co

Continental Insurance Co

Continental Oil Corp

Deere & Company

Dow Chemical Co

Eastman Kodak Co

General Electric Co

General Motors Corporation

W. T. Grant Co

Gulf Oil Corp

Hartford Fire Insurance Co

Humble Oil & Refining Co

Ingersoll-Rand Company

Inland Steel Company

International Business Machines Corp

International Harvester Co

International Nickel Co

Johns-Manville Corp

Kennecott Copper Corp

Monsanto Chemical Co

Montgomery Ward & Co

Mortbon Corp. of N. Y

National Lead Co

Newberry Co. (J.J.)

New Jersey Zinc Co

Owens-Illinois Glass Co

Penney Co. (J. C.)

Phelps Dodge Corp

Pittsburgh Plate Glass Co

Procter & Gamble Co

Pullman, Inc

St. Joseph Lead Co

Sears Roebuck & Co

Sherwin-Williams Co

Standard Oil Co., of California

Standard Oil Co. of N. J

Texas Corporation

Travelers Insurance Co

Underwood Elliott Fisher Co

Union Carbide & Carbon Co

United States Gypsum Co

United States Steel Corp

Westinghouse Air Brake Co

Westinghouse Electric & Mfg. Co

Woolworth Co. (F. W.)

Youngstown Sheet & Tube Co

Common Stocks — Sub-Total .

Preferred Stocks

American Cyanamid Co

A. T. & S. Fe pref . stock

Caterpillar Tractor Co., Cum. pref

Cons. Edison Co. Cum. pref. stock

Du Pont de Nemours, deb. Stock

J. I. Case Thresh. M. Co. pref. stock

Grant Co. (W. T.)

Northern States Power Co., Cum. pref

Union Pac. R. R., pref. stock

U. S. Steel Corp., pref. stock

Preferred Stocks — Sub-Total .

Common and Preferred Stocks — Funds Invested .

Aggregate Investments (Bonds and Stocks) .

Total Cost or

Value at Date

Acquired

$74,647.
55,667.50
24 , 530 .
15,895.
46,922.50
67,542.50

117,325.

102,642.50

102,472.

123,570.50
85,247.50
18,335.
46,943.50
26,691.30
83.732.50
19,793.50
47,194.
82,460.
83,492.

114,035.50
37,734.74
55,588.26
22,074.68
39,167.50
29,566.
75,010.
64,459.

122,972.50

110,434.
53,925.
94,155.
84,036.
72,223.63

39,598.
50 , 206 .
79,615.
73,887.

117,197.50
64,995.
64,340.25
28,112.50
41,972.50
57,662.50

106,337.50
85,129.47
69,165.

139,796.
95,588.26
50,071.21
62,592.50

135,711.50

104,184.
92,360.
12,587.75
70,572.
22,385.

108,879.75

3,973,431.80

1,230.

52,125.

6,772.

198,725.

116,125.

62,225.

7,642.76

103,000.

33,415.

715,173.50

1,296,433.26

5,269,865.06

35,462,732.30

XXX111

Real Estate and Equipment, Original Cost

Administration (October 31, 1938)
Washington, D. C.

Building, site, and equipment $756,544.44

Division of Plant Biology (September 30, 1938)
Palo Alto, California (Headquarters)

Buildings and grounds $154 , 941 .86

Laboratory 56,205.20

Library 30,126.77

Operating appliances 25,863 .37 267, 137.20

Department of Embryology (September 30, 1938)
Wolfe and Madison Sts., Baltimore, Maryland

Library 3 , 574 . 00

Laboratory 14 , 540 . 76

Administration 7,383.53 25,498.29

Department of Genetics (September 30, 1938)
Cold Spring Harbor, Long Island, New York

Buildings, grounds, field 292,433 .55

Operating 32,097.30

Laboratory apparatus 30 , 856 . 52

Library 47,182.74

Archives 45,488.90 448,059.01

Geophysical Laboratory (September 30, 1938)
Upton St., Washington, D. C.

Building, library, operating appliances 227, 121 .91

Laboratory apparatus 161 ,086.29

Shop equipment 19,508.95 407,717.15

Division of Historical Research (September 30, 1938)
Administration Building, Washington, D. C.

Operating 24,556.60

Library 8,497.21 33,053.81

Tortugas Laboratory (September 30, 1938)
Tortugas, Florida

Vessels 30,930.43

Buildings, docks, furniture, and library 12,930.86

Apparatus and instruments 9 , 322 .55 53 , 183 . 84

Department of Meridian Astrometry (September 30, 1938)
Dudley Observatory, Albany, New York

Apparatus and instruments 4 , 846 . 84

Operating 5,273.68 10,120.52

Nutrition Laboratory (September 30, 1938)
Vila St., Boston, Massachusetts

Building, office, shop, and library 133,887.27

Laboratory apparatus 37,116.14 171,003.41

Mount Wilson Observatory (September 30, 1938)
Pasadena, California

Buildings, grounds, road, and telephone line 222 , 688 . 94

Shop equipment 45 , 024 . 88

Instruments 669 , 383 . 19

Furniture and operating appliances 139,492.64

Hooker 100-inch reflector 627,149.01 1,703,738.66

Department of Terrestrial Magnetism (September SO, 1938)
6241 Broad Branch Road, Washington, D. C.

Building, site, and office 231 ,072.72

Survey equipment 101 , 904 . 01

Instruments, laboratory, and shop equipment 220 , 980 . 50 553 , 957 . 23

4,430,013.56
xxxiv

REPORT OF THE PRESIDENT

OF THE

CARNEGIE INSTITUTION OF WASHINGTON

FOR THE YEAR ENDING OCTOBER 31, 1938

REPORT OF THE PRESIDENT

OF THE

CARNEGIE INSTITUTION OF WASHINGTON

In accordance with regular procedure, the President
has the honor to transmit to the Trustees of Carnegie
Institution of Washington the following report concern-
ing problems and activities relating to work of the Insti-
tution in the year ending October 31, 1938.

Success in any great enterprise calls for such statement
of objectives as can be presented in generally intelligible
form. In practical operation, any large project develops
many collateral purposes in such ways as
Relation may confuse the issues unless care is taken
Research and to keep major objectives in view. It is also
o/Kn^wied^e to be expected that with change of condi-
tions as to time, place, and personnel, ad-
justment will be necessary if the main purposes are to
be followed. But somewhere it is essential that there be
always such awareness concerning the situation as may
prevent misguidance and distortion.

In founding the Carnegie Institution an agency was
set up in which the purposes were deliberately so defined
as to present a set of objectives quite different from those
of well known types of organization. And with this action
there arose need for intensive study of the opportunity
by all selected officers and those concerned with success
of the project. The general purposes of the Institution
as an agency devoted to " investigation, research, and dis-
covery, and the application of knowledge to the improve-
ment of mankind, " as defined by the Founder, conveyed

CARNEGIE INSTITUTION OF WASHINGTON

an idea of the objectives in a form intelligible to all. But,
just as in institutions devoted to higher education there
was much discussion as to means by which the defined
goals might be attained, so here, there has been natural
and proper consideration of means by which ideals of this
Institution could be realized.

Research of the constructive or creative or inventive
type covers a vast range of subjects and can be conducted
in a great variety of ways. Application of the results "to
the improvement of mankind' ' can be viewed again as pre-
senting a multitude of possibilities. To those who organ-
ized the beginnings of this great work the opportunities
seemed almost limitless. Most wisely they safeguarded
the program by insisting upon several principles which
were evidently in the mind of the Founder. One of these
concerned quality of projects, of persons involved, and of
materials made available for programs or projects; a
second general requirement expressed the need of striv-
ing for attainment of what is fundamental as, over the
years, the best means of advancing knowledge. With
reference to application of results, the statement regard-
ing " improvement of mankind" seemed clearly to en-
visage a process of advancing development of mankind,
in which work of the Institution would be contributing
to those more fundamental aspects of life out of which
improvement grows or is built. So, among his last utter-
ances on these subjects, Elihu Root voiced the hope for
such continuing absorption of the results in advance of
knowledge into the thought of the people as would permit
building to higher and higher levels of thought, apprecia-
tion, and belief.

REPORT OF THE PRESIDENT, 1938

Among the problems necessarily involved in the pro-
gram of an institution of this nature, one of the most fun-
damental concerns the relation between that form of in-
tensive investigational activity commonly thought of as
representing research, and the type of constructive ac-
tivity known as organization of knowledge. We know
well the contributions of constructive or creative work
reaching into fields of the unknown and making new mate-
rials available. Organization of knowledge is recognized
as opening visions of the whole field, and sometimes lead-
ing to such glimpsing of relations between areas of knowl-
edge as makes possible the formulation of great generaliza-
tions or principles. The first activity has been recognized
as contributing enormously to increase of information;
the second is seen to give acquaintance with relationships
or principles which are among the greatest values in
knowledge.

Depending upon the importance of factors having spe-
cial significance at a given time, knowledge may seem
to be advancing either by reason of particular intensive
researches, or because of emphasis on newly developed
organization of information. Unless the whole field of
learning be examined with reference to all of the types
of creative work, it would be easy for difference of opin-
ion to develop concerning the activities through which the
more significant advances are made.

Prom one point of view, it would be possible to indicate
that the degree of intensiveness of research in limited
fields determines the rate of progress. If this were true, it
might be desirable to organize investigational programs in
such a manner that emphasis would be placed mainly on
concentrated attack upon limited problems, in the hope

CARNEGIE INSTITUTION OF WASHINGTON

that through such effort the whole range of knowledge
would, in time, be furthered most effectively.

On the other hand, argument might be made that unless
the results coming out of intensive research are related to
comparable materials from other fields a very large
part of all that could be known through the interlocking
of contributions might never appear. Argument might
also be made in favor of the view that it is the clear vision
of knowledge organized with reference to particular prob-
lems that gives us the principles which become the foun-
dations upon which research is built. So, in the field of
biology, the general law of evolution is a type of idea
which has given tremendous stimulus to study of life in
practically every realm. Or, in the inanimate world, the
law of gravitation is a foundation upon which much of
research on the visible universe must stand.

Experience in many kinds of institutions concerned
with research, and with knowledge broadly, indicates that
the most effective organization, and the most economical
scheme of operation, is one in which there is careful bal-
ance between activities devoted to intensive or concen-
trated research and those giving vision over larger areas,
covered in such manner as to obtain the major generaliza-
tions coming out of special activities, as also the largest
values from the individual researches.

It is true that the term " proper balance" will neces-
sarily be defined according to conditions at a particular
period or place. And as these conditions vary the em-
phasis on different parts of the system will be modified
to advantage. It is also true that the question of balance,
and in some ways of the wider and deeper perspective
involved, has greatest significance in connection with in-

REPORT OF THE PRESIDENT, 1938

stitutions which represent a considerable variety of sub-
jects.

Realizing that the significance of perspective is most
clearly appreciated where the spread of subjects or activi-
ties is wide, it is important to keep in mind the fact that
in the areas of research covered by the Carnegie Institu-
tion of Washington the range of interests extends from
the most intimate details of atomic physics out through
chemistry, biology, and history up to the threshold of
investigations directed more particularly at inquiry con-
cerning human life and activities.

It is interesting to note in this connection that at vari-
ous times in the history of science, and of philosophy, and
also of religion, there have developed definite expressions
of the idea of unity, including everything in the physical
and biological universe, not only in space but through
time. As knowledge advances, this idea of unity becomes
in the scientific sense an increasingly practical feature
of research on the organization of knowledge. It is no
longer possible to study the broader problems of astron-
omy and the universe without recognition of an inter-
relation among the elements of the world about us wher-
ever we touch them. In the same manner it is discovered
that study of events in geological history, even for re-
mote periods, is based upon application of principles
which extend through time, and may be carefully exam-
ined in the world today. Again, in consideration of the
problem of development of life or evolution, investiga-
tion of the various stages in the process is based upon
the idea of growth through the years in materials which
have a continuity and are, so far as we know, affected in
comparable ways by influences through space and time.

CARNEGIE INSTITUTION OF WASHINGTON

In attempting to reach an adequate understanding of
relations between widely separated types of researches it
invariably becomes important to have each and all of the
problems involved stated in such manner that the essen-
tial elements are intelligible to investigators interested in
determining the connection or relation among these vari-
ous aspects of nature. Results from the most intensive re-
search will commonly and naturally be expressed in terms
of formulae and shorthand methods^ developed in order to
permit the investigators to work rapidly and exactly,
without the limitations imposed by long and perhaps com-
plicated statements or explanations. Frequently these
formulae are not understood by investigators in other
fields, and it becomes important to find some means by
which the essential elements of the contributions can be
made available to others.

There is much difference of opinion as to how inter-
pretation of basic scientific data may best proceed. Some-
times it is accomplished by what may be called a matter-
of-fact statement, which gives details that can be de-
fended from the point of view of the investigator, but
which has no vital meaning to students of other problems
or of human interests widely. Sometimes it is possible to
look into deep reaches of a particular field and appear
to visualize the materials represented, but in many cases
the result has no greater significance in terms of intel-
lectual progress than the impact of light rays picturing
a particular landscape on the retina of an ox. There must
be some conscious relation of the elements represented to
each other, or in the sense of research and knowledge
nothing happens.

REPORT OF THE PRESIDENT, 1938

In the case of phenomena such as those of the Grand
Canyon observers may look into the depths of the great
gulf, with its rugged and spectacular walls, and of fifty
persons receiving the same picture on the retina only one
or two may have a sense of understanding of what it
means. Another person may come who fits the various
elements together and who brings out of his experience
the beauties of color and form, the grandeur of height
and of mass, and with this the sublimity of power and of
changes in the past which have produced these effects,
and at the same time have recorded the lapse of ages,
constituting one of the most important elements of the
picture. As yet we have made only too little progress in
the attempt to find the way to interpret the facts of science
so as to make them intelligible, not merely to the public,
but to investigators in other fields of research as well. In
reality this constitutes one of the major problems involved
in consideration of the future of science and of knowledge.

Granted that we become expert in the simple and clear
interpretation of data in the various fields of research, it
becomes possible then to bring the pictures of these as-
pects of research together, and to form opinions concern-
ing their relation to one another; thus bringing about
relation of materials which may furnish the foundations
for generalizations ; the generalizations in their turn con-
tributing toward interpretation of details in other fields.

So there is reason to believe that in any scheme by which
we attempt to secure the fullest values through research,
and from the organization of knowledge, we will be de-
pendent to a considerable extent upon our ability to inter-
pret the details in such form that they may be fitted into
the general setting, and thus help to advance those gen-

CARNEGIE INSTITUTION OF WASHINGTON

eralizations which may become fundamental principles
of science.

As the program develops, it becomes increasingly clear
that one function of the Carnegie Institution lies in mak-
ing possible such relation of its various types of special-
ized research to one another as will bring largest values
for each research, and will also facilitate building upward
in the broader scheme of knowledge. This process will
depend in some measure upon acceptance of the idea that
all elements of nature, and of knowledge, have interrela-
tionships. We now realize that no science can exist alone ;
no branch of knowledge can exist alone ; all must be related
to other knowledge if they are to attain their largest value.

Illustration of ways in which ideas expressed above are
found to work out in practical operations of the Insti-
tution is furnished by types of activities presented in

a Division our conferences, as well as by programs of

Conference annual meetings, for which such excellent
facilities are available in Elihu Root Hall with the ex-
hibit rooms and conference rooms grouped around it.

It is the custom of the Division of Animal Biology to aid
in advancing development of special investigations, as
also of broad interpretations of phenomena covering
more than one group, by arranging conferences for all of
the departments and special investigation groups com-
prised in the Division. These gatherings occur at the
laboratories of the departments, and are so arranged that
meetings pass in rotation through the major groups. Illus-
tration of the mode of procedure, and of the influence of
such gatherings, is furnished by the conference of the
Division held at Cold Spring Harbor on October 28th of

REPORT OF THE PRESIDENT, 1938

this year. Meetings of similar type, but with somewhat
different organization, are held also from time to time by
other Divisions and groups of the Institution.

The Cold Spring Harbor conference of October 28th
was attended by representatives of the departments or
groups of Genetics, Eugenics Record Office, Embryology,
Nutrition, and Tortugas Laboratory, together with Re-
search Associates, and with them collaborating investiga-
tors from a considerable number of institutions. Mem-
bers of the staff at Cold Spring Harbor participated in
the proceedings, and a group of staff members was pres-
ent also from the other departments and groups. The
conference included a preliminary period without special
program, in which the investigators could discuss prob-
lems of mutual interest without the restrictions of a de-
tailed plan. A formal program was initiated at 11:00
o'clock by presentation of seven papers on special sub-
jects. Four of these were prepared by members of the
staffs of departments, two by Research Associates, and one
by a collaborating investigator. The papers were all care-
fully prepared, and eventually all will be published, either
as separate articles or included in more extended studies
or reports. The list is as follows :

M. Demerec — Nature of X-ray Induced Hereditary Changes in Dro-
sophila.

C. B. Bridges — Constitution of Germ Plasm in Relation to Heredity.

E. C. MacDowell — Leukemia Studies with Heat and with Trypan

Blue.

0. Riddle — Regulation by the Anterior Pituitary.

H. H. Laughlin — Blood Kinships within Eight Degenerate Families.

E. W. Sinnott — The Effect of Polyploidy on Fruit Shape in Cucurbits.

H. C. Sherman — Influence of Nutrition upon Body Composition.

CARNEGIE INSTITUTION OF WASHINGTON

Bach paper was limited sharply to a time within fifteen
minutes, after which there was opportunity for discus-
sion. The program was brought to a close in time for
luncheon, at which the investigators gathered in the
dormitory of the Department of Genetics.

Following luncheon, visitors were invited to study and
to discuss exhibits by the investigators representing va-
rious divisions of work being conducted at Cold Spring
Harbor. The extraordinarily well planned materials were
described briefly by the persons in charge, and there was
free discussion of the problems illustrated and their ulti-
mate significance. Of the twenty exhibits available for
study by visitors, the following illustrate the types of
research :

A. D. Bergner — Types of chromosomal deficiencies due to colchicine

treatment.
S. Satina — Identification of specific chromosomes in pollen grains.

A. G. Avery — a. 15-year breeding records showing effect of different

extra chromosomes upon size of seed, percentage of germina-
tion, viability, and spontaneous non-disjunction,
b. Method of securing homozygous races through doubling chro-
mosomes of haploids by colchicine treatment.
H. E. Warmke — a. Sterile hybrids made fertile by chromosome
doubling,
b. Somatic criteria of polyploids in different species.
E. W. Sinnott and Miss Hoskins: Effect of polyploidy upon fruit

shape in squashes.
C. B. Bridges — Vestigial deficiency.
M. Demerec and Miss Hoover — Hairy wing duplication.

B. P. Kaufmann — An induced reverse repeat.

E. C. MacDowell — Details of leukemia studies with heat and with

trypan blue.
R. W. Bates — Factors affecting the response to prolactin.

a. Sex hormone treatment.

b. Sex difference.

REPORT OF THE PRESIDENT, 1938

Dr. Schooley — Relations of pituitary to size of body and viscera.
Dr. Schooley and Mr. Lahr — Hormonal basis of maternal behavior
and broodiness.

a. Maternal behavior in rats.

b. Coincidence of prolactin-release (colchicine technique) with

beginning broodiness in pigeons.

c. Broodiness in doves with progesterone treatment.

Dr. Schooley and Dr. Miller — Cytology of pituitary and adrenal.

a. Formation of new cells in anterior pituitary.

b. Cytological changes of adrenal cortex in experimental animals.
Mrs. Smith — Relations of the pituitary to heat production in pigeons.

a. Effects of intermedin and "adrenotropin" on basal metabolism.

b. Influence of prolonged fasting on the basal metabolism of

normal and hypophysectomized animals.

0. Riddle — On relation of pituitary hormones to carbohydrate and
calcium metabolism.

C. B. Davenport — Changes in head-form during post-natal develop-
ment.

Barbara S. Burks — Autosomal linkage in man.

H. H. Laughlin — Blood kinship of a selected-near-kin to the subject-
individual, and the degree of development of the subject-trait in
such selected-near-kin, as two computable factors in the predic-
tion of development of the subject-trait in the subject-individual.

In the course of examination of the exhibits there was
much discussion of relation between the investigations, as
also concerning relation between problems presented by
the researches at Cold Spring Harbor and those of other
departments of the Division. Altogether it was evident
that there was not only sharpening of the incisiveness in
research with reference to individual projects, but that
there was a marked broadening of view regarding the
whole problem of animal biology, with the possibility that
entirely new and important problems might arise out of
the discussion.

CARNEGIE INSTITUTION OF WASHINGTON

' In discussion regarding future problems of the Institu-
tion, in 1930 attention of the Trustees of the Institution
turned toward the need for increase of facilities in the

EHhu Root Administration Building to be used in con-
Hal1 nection with service to the public through
interpretation of research results by lectures, conferences,
exhibitions, and publication. It was proposed then that
additional space be provided for conference rooms, for of-
fices to be used by visitors engaged in research and by mem-
bers of the staff temporarily in residence in Washington
for research purposes, for additional auditorium space
for general lectures, and for facilities such as would per-
mit exhibition of research results without requisitioning
office quarters of the administration staff. In 1931, on
recommendation of Senator Root, an initial appropria-
tion of $30,000 was made toward a building fund to carry
out these plans. In that year distinct advance was made
in the whole program of public relations, and there was
record of further progress toward a building scheme in
the purchase for this purpose of a tract of ground con-
sisting of four lots immediately to the east of the Ad-
ministration Building.

The proposed building program was discussed through
several years following acquisition of the first additions
to the building area needed, but the generally unfavorable
financial situation made it necessary to move slowly in
accumulation of funds for this purpose. In this period
Senator Root frequently expressed the opinion that the
project was of the first order of importance to the Insti-
tution and was a type of activity which Mr. Carnegie
would have wished to see advanced. In 1936 the Execu-
tive Committee took action to realize the building project

REPORT OF THE PRESIDENT, 1938

with the purposes as defined. It voted from the Special
Emergency Eeserve Fund a sum of such limits as would
be adequate for the project and made funds available for
initiation of the program as early as possible. As Senator
Root was not present at the meeting at which this action
was taken, two members of the Committee were delegated
to call upon him at once and announce effective realization
of the plan in which he had taken such deep interest.

Building operations began in September 1937, under
the guidance of Mr. William Adams Delano as architect
and have proceeded to completion and occupation in ample
time for activities connected with the annual meeting in
1938. Fitting well to the original Administration Build-
ing erected in 1908, and yet possessing a degree of indi-
viduality, the new quarters are dignified and artistically
pleasing throughout. The carefully planned offices meet
a need which had been recognized only in part by the staff
by reason of its effort to make the best of some rather
difficult situations in the past. The space designed for
use in connection with exhibition arrangements is not only
much superior to what has been available heretofore, but
it permits these activities without dispossessing important
staff officers of the Institution of their quarters at such
times as the annual meeting, when it is desirable that they
have favorable opportunity for consultation with Trus-
tees, visiting directors, and staff members.

Readjustment of space use in the older part of the build-
ing makes possible utilization of rooms for the Division
of Historical Research, and other space is prepared for
distinguished investigators of our staff and from other
institutions who visit us each year. Quarters for the pub-

CARNEGIE INSTITUTION OF WASHINGTON

lications staff are adequate for the first time, and greater
effectiveness in operation is at once apparent.

To the auditorium in the new quarters the Trustees, on
motion of Governor W. Cameron Forbes, have given the
name Elihu Root Hall, and upon this part of the struc-
ture the greatest possible care has been bestowed, in order
that it may serve to express appreciation of Senator
Root's service to the Institution through the thirty-five
years of his trusteeship, and his continuing contribu-
tion toward improvement and clearer statement of the
ideals and objectives of the Institution. Of modest and
yet adequate size, the auditorium furnishes opportunity
for better discussion of results in research than has here-
tofore been possible. A Committee of the Trustees gave
special attention to decoration of the room. The results
attained under direction of Mr. William Adams Delano,
the architect, and Mr. J. Monroe Hewlett, the artist, con-
stitute a real contribution to the application of art to use
in cooperation with science.

Completion of the new quarters available for advance
of conferences and for interpretation of research opens
the way to new and better opportunities, not only for edu-
cation, but, in an even wider field, for organization and
advancement of knowledge.

The types of activity that center in Elihu Root Hall,
with the exhibition and conference rooms grouped around
it, have given in recent years an important opportunity in
the Institution for conference and discussion on both spe-
cial and general subjects. The assembled exhibits always
represent some of the most important researches from
each group, shown under the most favorable conditions for
interpretation. It has become a habit for the entire group

REPORT OF THE PRESIDENT, 1938

of exhibitors to go through the whole exhibition together,
with each person explaining his materials to the others.
The mutual education accomplished has led to many dis-
coveries of relationships in research, and to development
of not a few new joint investigation projects. Just as
the division conference has served to interpret and to edu-
cate a considerable group to advantage of the individual
investigator, so the general Institution exhibition has per-
formed a similar service for the whole Carnegie Institu-
tion staff, including officers, Trustees, and distinguished
guests.

The possibilities of Elihu Root Hall, together with the
equipment of the new quarters, for performing large
service to the public, such as seems a natural responsibility
for an agency like the Carnegie Institution, must be con-
sidered of great significance. In developing the policy of
presenting interpretations of research in the form of
press releases, it was assumed that the principal objectives
would concern the considerable group of widely-reading
persons not especially interested in conduct of research.
But, to the surprise of those examining the situation, it
appeared that the first important evidences of approval
came not so often from the lay reader, or from the
applying engineer, as from investigators in other fields.
It seemed, then, that the interpretation program was serv-
ing a purpose of importance in relating to each other
researches of the intensive type, for study of which one
would at the outset expect only a limited audience. It
appeared that in these operations contribution was being
made to interrelation of projects and their results, which
is to be desired in a world characterized by unity of
nature, and that these are logical steps toward organiza-

CARNEGIE INSTITUTION OF WASHINGTON

tion of knowledge so clearly essential in any major plan
for aid in advancement of learning.

With the evident multiplicity of important investiga-
tions under way within the program of the Institution it
has never been possible in the special statement made by
■ . M the President, to touch more than a small

§D6Cld.l Posses

of Research part of those having immediate signifi-
cance. It is, moreover, to be noted that the
Year Book, which becomes available to the Trustees on the
day of the annual meeting, contains report on the entire
program, and that volume as a whole constitutes the real
report of the President. The increasing simplification of
departmental reports by the directors has contributed
in an important way to the possibilities of reviewing the
year's activities. It is also desirable to note that the bibli-
ography, comprising pages 406 to 432 in the Year Book,
covers the results in publication of the past year, and fur-
nishes an important picture of the program as a whole.
Without making distinctions concerning ultimate val-
ues, there are among contributions completed or brought
to climax in the last year a number of investigations which
may well receive special mention.

MOUNT WILSON OBSERVATORY

In the field of astronomical research no record of the
year would be complete without mention of the finished
and published report on Magnetic Observations of Sun
Spots, 1917-1924, by Dr. George E. Hale and collabora-
tors, representing the results of many years' work by him
and his associates, and appearing now after many years'
preparation. The publication of this great work, brought

REPORT OF THE PRESIDENT, 1938

to conclusion by Dr. Seth B. Nicholson, constitutes one of
the notable achievements in astronomical research.

Part I describes the solar telescopes of Mount Wil-
son Observatory and gives the history of their develop-
ment. The observations and theories which led to the
discovery of magnetic fields in sunspots are discussed;
and the methods and equipment used in measuring their
field strengths and polarities are described in detail. A
scheme for classifying sunspots magnetically is given and
all the spot-groups observed from 1917 to 1924, inclusive,
are classified for each day. A law describing the magnetic
properties of sunspots is deduced from the observations.

Part II contains the daily magnetic observations of
each sunspot observed from 1917 to 1924. The observa-
tions are recorded on drawings of the solar disk repro-
duced on a scale of seven inches to the sun's diameter.

Dr. Hale's great contribution to study of sunspot phe-
nomena, described in detail in the foregoing publication,
came as a direct consequence of his interest in the im-
provement of instrumental facilities and his remarkable
skill in the designing of new apparatus. Dr. Adams in an
article in Astro physical Journal, May, 1938, comments
upon this characteristic of Dr. Hale, saying :

"The invention of the spectroheliograph and the spec-
trohelioscope and the adaptation of the tower telescope
and the vertical spectrograph for solar investigation are
excellent examples of this quality of Hale's mind. In
part it was probably due to his engineering training, but
much more to his appreciation of the enormous impor-
tance of the value of improved instruments to astronom-
ical progress, and to his creative ability and love of fine
workmanship. He took immense pleasure in seeing a new

CARNEGIE INSTITUTION OF WASHINGTON

instrument assume form; and, as he often said, 'Had I
not been an astronomer, I should have liked to have been
an instrument-maker.' "

Continuing comment upon Dr. Hale's recognition that
advance of research on astrophysical problems could be
gained only through improvement of the tools used by
the investigators and through the development of new
and more powerful instruments Dr. Adams writes :

"The establishment of the Mount Wilson Observatory
gave Hale, for the first time, the opportunity of building
instruments on a large scale to fit the problems to be
investigated rather than of finding the problems to be
undertaken with an existing instrument. This is the point
of view of the physicist and was a principle maintained
by Hale throughout his life. The Snow telescope was
designed for certain specific purposes, primarily to make
possible the use of larger spectrographs and the violet
region of the spectrum; the 60-foot tower telescope, to
improve seeing conditions on the sun's image and afford
convenience of operation and temperature control for
very long spectrographs; and the 150-foot tower tele-
scope, to afford a very large solar image for the study of
sunspots and details on the sun's surface.

"The same attitude was taken with reference to the
stellar instruments, the 60-inch and 100-inch telescopes
being designed for use at three foci, so that the magnifica-
tion and the auxiliary instruments could be adjusted to
the problem in mind. Hale was always greatly interested
in the coude form of the reflecting telescope, appreciat-
ing from experience the value of large-scale stellar spectra
and the immense advantages of fixed instruments oper-
ated under laboratory conditions."

REPORT OF THE PRESIDENT, 1938

In tracing the steps leading up to Dr. Hale's great dis-
covery, steps described at length in the publication above
referred to, Dr. Adams says in part :

"Hale started with the simple and altogether natural
working hypothesis that the differences of intensity be-
tween the same lines in spots and on the disk of the sun
are due to the lower temperature of spots. Accordingly,
an investigation was begun in the laboratory to study the
effects of temperature on the spectra of various elements.
The arc spectrum of iron was photographed, first with a
rotating arc, then in an arc through which currents of
widely varying amount could be passed, and finally in the
outer flame and in the central core of an arc.

i t rQ^ results were decisive in showing a great difference
in behavior among the lines, some being relatively strong
in the spectrum of the low-current arc and the cooler outer
flame, while others were strong only in the hot central
core and in the high-current arc. Comparison with the
spectrum of sunspots at once showed that the ' low-tem-
perature' lines of the laboratory were just those which
were greatly strengthened in spots while the ' high-tem-
perature ' lines were but little affected. The final evidence
that the effect was due to temperature was provided by
a simple electric furnace, which gave results precisely
similar to those found with the arc.

"This investigation was of great importance not only
because its results explained many of the most important
phenomena of sunspots but also because it had far-reach-
ing consequences. The classification of lines according
to temperature behavior made at this time, and improved
and greatly extended by King with the electric furnace,
laid the foundation for much of the analysis of spectra in

CARNEGIE INSTITUTION OF WASHINGTON

later years. The discovery of the weakening of the en-
hanced lines in sunspot spectra and the ensuing laboratory
investigations led to the suggestion that low density might
be favorable to the production of enhanced lines, a conclu-
sion so fundamental in the theory of ionization. Finally,
these results had extremely wide applications to stellar
spectra, aiding in determinations of temperature and
density, and through successive stages leading to the spec-
tral differentiation of giant and dwarf stars and the dis-
covery of the spectroscopic method of determining
parallaxes.

" Observations with the spectroheliograph were contin-
ued regularly by Hale and Ellerman during these years
at Mount Wilson, and some experimental work with this
instrument led to results which culminated in Hale's most
brilliant discovery. Sufficient progress had been made in
sensitizing photographic plates to red light by means of
dyes, especially by R. J. Wallace, to permit the use of the
spectroheliograph with the a line of hydrogen.

" Photographs with this line at once showed a variety
of detail, both in dark and bright flocculi, which had not
been seen previously in observations with the H$ line.
Most important of all, Hale's skilful examination at once
detected in the curved form of the flocculi about sunspots
evidence of vortical motion. Further observations fully
confirmed this opinion, in one case a very long dark floc-
culus, which showed gradual curvature as it approached
a double spot, finally forking and being drawn into the two
centers of the vortex. That he foresaw at once the conse-
quences of this discovery is shown by two quotations from
his article on solar vortices :

" 'In view of the fact that the distribution of the hydro-

REPORT OF THE PRESIDENT, 1938

gen flocculi frequently resembles that of iron filings in a
magnetic field, it is interesting to recall the exact corre-
spondence between the analytical relations developed in
the theory of vortices and in the theory of electromag-
netism.

" ' Double lines, which look like reversals, have recently
been photographed in spot spectra with the 30-foot spec-
trograph of the tower telescope, confirming the visual
observations of Young and Mitchell. It should be deter-
mined whether the components of these double lines are
circularly polarized in opposite directions, or, if not,
whether other less obvious indications of a magnetic field
are present. I shall attempt the necessary observations
as soon as a suitable spot appears on the sun.'

"On June 25, 1908, Hale obtained a series of photo-
graphs with the 30-foot spectrograph, using a Fresnel
rhomb and Nicol prism. These gave unmistakable evi-
dence of the Zeeman effect and of the presence of a mag-
netic field in sunspots.

"Following this remarkable discovery, Hale devoted
considerable time to measurements of the strength of field
in spots, comparisons with laboratory results, studies of
plane polarization across the lines of force, and experi-
mental work on vortex models. Since the resolution of
the components of many of the spot lines was beyond the
power of the 30-foot spectrograph, he decided to postpone
further extensive investigations until the completion of
the 150-foot tower telescope and the 75-foot spectrograph,
which were under construction in 1909 and 1910. The
decreasing sunspot activity, however, and the scarcity of
spots led him at this time to undertake an investigation
particularly well suited for sunspot minimum but ex-

CARNEGIE INSTITUTION OF WASHINGTON

traordinarily difficult and exacting because of the small-
ness of the quantities involved. This was the problem of
the existence of a general magnetic field of the sun as
shown by the Zeeman effect. Here there could be no ques-
tion of the separation of lines into components, but, as
computation showed, only of minute displacements, when
the Nicol prism was rotated, of three or four thousandths
of a millimeter even on the great scale of the spectra with
the 75-foot spectrograph. A large amount of observa-
tional material was required, and the measurements were
undertaken by van Maanen and other members of the
Observatory staff.

" Positive results were obtained which were discussed
by Hale in an extensive article written in March, 1913 ;
but the problem was rendered even more difficult by the
apparent failure of certain lines to show the expected
effect. The investigation was continued by Hale up to
the end of his life, and he developed several ingenious
and effective devices for measuring the minute quantities
involved. New series of photographs were obtained near
the sunspot minima of 1922 and 1932; and the spectra
were measured, but with somewhat inconsistent results.
It is very difficult to draw a definite conclusion regarding
the outcome of this long research undertaken with such
great skill and patience. The presumption for the exist-
ence of the general magnetic field seems to be strong, but
the definite proof may have to await new methods or im-
proved instruments."

Reference in the foregoing statement to the part played
by instrument improvement in the progress of astronom-
ical research suggests mention of the fact that after many
years of constant use the 60-foot tower telescope is now in

REPORT OF THE PRESIDENT, 1938

process of reconstruction. When the remodeling is com-
pleted, this telescope, the first instrument of the type ever
built, will include features of convenience suggested by
past experience and others made possible by modern de-
velopments in science and industry.

The mountings of the ccelostat and second flat mirrors
are being redesigned, a new drive installed, and many
features added to provide for the automatic registration
of the sun's image throughout the day. The mounting
of the 10-inch photographic telescope is also being remod-
eled and a photovisual objective has been designed to aid
in the photography of object-prism spectra in the yellow
and red region.

Respecting the investigational work of the staff for the
year Dr. Adams' report shows that gratifying progress
has been made in all of the projects constituting the
Observatory program.

The year has been especially propitious for conduct
of the various researches relating to solar phenomena be-
cause of unusual disturbances in the sun that have been
taking place. The number of sunspot groups observed
during the year, for example, is the greatest since the
Observatory was established. Moreover, the largest
groups of the year, groups which crossed the sun's central
meridian on July 28 and October 4, 1937, respectively,
were among the six largest groups that have ever been
observed at the Observatory.

Spectrograms of several large stable sunspots were
obtained for use in the photometry of the spot spectrum.
Four selected regions were photographed on successive
days, when the observing conditions were excellent, as the
spot moved from east to the west limb. Much informa-

CARNEGIE INSTITUTION OF WASHINGTON

tion concerning the structure of sunspots may be obtained
from spot spectrograms taken in this way.

The f aintness of rare-earth lines in the solar spectrum is
well known, and most of those hitherto identified belong to
the ionized atom. With the aid of laboratory data on
europium, which has been obtained, more than 20 of the
neutral lines of this element have been identified with
faint solar lines. This increases the known singly ionized
europium lines in the sun from 5 to 27.

An eruptive prominence, observed on March 20, rose in
two and one-half hours to a record height, falling just
short of a million miles or about one and one-eighth times
the sun's diameter. Analysis of the motions gave three
successive velocities of 42, 85, and 125 miles per second.

Dr. Edison Pettit, who has been studying these eruptive
prominences for many years, spent three of the summer
months at the McMath-Hulbert Observatory collabo-
rating with Mr. R. R. McMath in study of prominences.
This is the only observatory equipped to take motion-
pictures of the sun. Previous experience has however
shown that in such study the motion-picture equipment
gives results of definite value. During his stay seven
eruptive prominences were observed and motion-pictures
taken of them, making a total of nine for the year, the
largest number ever observed, the average for 50 years
being one per year.

The prominence observed on September 17, 1937, rose to
a height of 625,000 miles, with observed velocities, approx-
imately, of 18, 36, 115, 340, and 455 miles per second.
Observations of this prominence reduce the time interval
required for a velocity-change from the previous estimate
of 5 to 10 minutes to less than 45 seconds.

REPORT OF THE PRESIDENT, 1938

Dr. Pettit reports that continuous observation of an
active prominence over a considerable period occasionally
reveals faint streamers, unconnected with the prominence,
entering the center of attraction from high up in the
coronal region. About a dozen of these " coronal" promi-
nences have been observed and five have been measured in
detail.

Over an active sunspot group small, nearly round
masses of chromospheric matter occasionally shoot out
and, unlike the surges, do not return. These " ejections"
are usually very faint, many being at the limit of vision on
the films. Aside from surges and ejections, all motions in
sunspot prominences are downward to the spot.

Ordinarily, streamer formations above a sunspot are
preceded by the appearance of a bright, nearly round
cloud, which feeds the streamers extending from one side
of the cloud to the spot area. Sometimes the cloud elon-
gates and feeds streamers from both ends, the prominence
matter moving down both branches of the loop. Such loop
formations are frequently seen over sunspot groups.
Particular attention is being directed to these streamer
formations in the attempt to determine their significance.

Recent discovery of the tenth and eleventh satellites
of Jupiter by Dr. Seth B. Nicholson, and further obser-
vation on the ninth satellite constitute an important ad-
vance in the study of planets and the bodies accompanying
them.

In the first order of interest among natural phenomena
has been also the continued investigation of novse and
supernovse, among the most mysterious and interesting
and ultimately probably some of the most important
objects of astronomical research. Refined methods of

CARNEGIE INSTITUTION OF WASHINGTON

spectroscopic study in this field have given materials
of much interest, and researches of this type are held to
represent a field of exceptional promise for the future.

Dr. F. E. Wright, Chairman of the Committee on Study
of the Surface Features of the Moon, has completed the
series of visual measurements of the percentage amount of
plane polarization in light diffusely reflected by lunar and
terrestrial materials and is now preparing the report on
the results. To study the polarization of moonlight and
of sunlight diffusely reflected by terrestrial substances, a
new high-gain, alternating-current amplifier has been
constructed in the laboratory of the Department of Ter-
restrial Magnetism from designs by Mr. Ellis Johnson of
that Department. The instrument is used with a rotating
Mcol prism (10 cycles per second) and furnishes an inde-
pendent check on visual measurements. Preliminary
tests indicate that it operates satisfactorily and has ade-
quate sensitivity for the measurement of the intensity of
the polarized component of the incoming beam; it also
measures the total intensity of the incoming beam, but
with smaller precision.

During July Dr. Wright photographed the lunar sur-
face at brief intervals throughout the full lunation taking
500 pictures in so doing. The photographs were made at
the Newtonian focus of the 100-inch reflector with the aid
of a zero corrector, which functions extremely well over
the spectral range X -5000- X 6000, and will form the basis
for a topographic reconnaissance map of the central por-
tion of the moon.

In study of galactic nebulas Dr. Walter Baade has con-
tinued his program of direct photography through red
filters, giving special attention to the region of the galactic

REPORT OF THE PRESIDENT, 1938

center. The investigation is of exceptional importance
because it has partially penetrated the heavy obscuration
that hides the nucleus of our system. A survey in dupli-
cate (red and blue) of the region galactic longitudes 300°
to 350°, latitudes + 8° to — 8°, made with the 18-inch
Schmidt reflector on Mount Palomar, fully confirms the
strong selective absorption reported a year ago. The
greater space penetration of the red films, relative to the
blue, introduces marked differences in the pattern of
obscuring clouds. Further, various faint extended nebu-
losities, absent or inconspicuous in the blue survey, are
well recorded in the red, presumably by strong Ha emis-
sion. For instance, NGC 6357, of which only one or two
small wisps appear in the blue, is an outstanding object on
the red films, rivaling in size the Orion Nebula and Mes-
sier 8. Among a number of new clusters found during the
survey, subsequent checks with the large reflectors dis-
closed half a dozen very heavily obscured globular
clusters.

Dr. Baade states that one difficulty encountered in this
work is due to the variable, and sometimes heavy, sky fog
appearing on the red films after only moderate exposures.
Since the fog on a given night is a function of zenith dis-
tance, its source must be atmospheric — probably the red
auroral lines. It seems possible, he thinks, that the occa-
sional difficulties encountered during the past half-year
may have been due largely to the high frequency of sun-
spots, now near maximum. To test this point a spectro-
scopic investigation is now under way.

In study of the extragalactic nebulas the major develop-
ment during the past year has been the cooperative study
of two supernovae in a manner more detailed and compre-

CARNEGIE INSTITUTION OF WASHINGTON

hensive than has hitherto been possible. Supernovae
represent the sudden release of energy on a scale which far
transcends that of any other known phenomenon (one of
the two recent supernovae reached a maximum luminosity
of the order of 109 suns). For the first time, sufficient
information has been assembled to investigate, rather
than to speculate upon, the behavior of matter and radia-
tion under the extreme conditions represented by the
explosions.

In the general field of extragalactic research, emphasis
has been shifted from the study of the observable region
as a sample of the universe, to the detailed investigation of
nebulae as stellar systems. The problems of nebular struc-
ture and evolution have replaced, for the time being, the
problem of cosmology.

During the year an extensive observing program was
finished by Dr. Edwin P. Hubble which was undertaken
for the purpose of obtaining good photographs with the
large reflectors of the 800 nebulas in the Shapley-Ames
catalogue, north of declination minus 30° and equal to or
brighter than the limit of completeness at photographic
magnitude 12.9. The task of enlarging the Mount Wilson
collection of photographs to meet these specifications has
required the cooperation of several observers over a pe-
riod of years. In the course of this and other more special
programs, photographs of many fainter nebulae have also
been assembled until the collection now includes about
2000 NGC objects and nearly 1000 given in the IC.

Since the material is complete for the brighter nebulae
(over three-quarters of the sky) and probably representa-
tive for the fainter objects, attention has now been di-
verted from the compilation to the analysis of the data.

REPORT OF THE PRESIDENT, 1938

The investigations include detailed, quantitative studies
of the sequence of classification, of the relative frequen-
cies of various types, and of the small-scale distribution of
nebulas.

Dr. Adams reports that the new auditorium and exhibit
hall on Mount Wilson, which were completed last year, are
serving admirably the purpose for which they were in-
tended. The exhibit of astronomical photographs, shown
as transparencies, is open to the public on Friday eve-
nings and for an hour each afternoon. The dome of the
100-inch telescope is also opened each afternoon and the
mechanism and operation of the instrument are explained
to visitors. Friday evenings an illustrated lecture is given
in the auditorium preceding the demonstration at the
60-inch telescope, to which visitors are admitted on these
evenings. In the summer months, when the crowds are
large, visitors who cannot gain admission to the lecture
hall go at once to the 60-inch telescope. During the year,
11,191 visitors were admitted to the 60-inch telescope for
the Friday evening demonstration — 1000 more than for
the preceding year, in spite of the fact that for three
months Mount Wilson was inaccessible to the public
because of storm damage to the Angeles Crest Highway.

THE GEOPHYSICAL LABORATORY

In reporting upon the work of the Geophysical Lab-
oratory for the year just closed, Dr. L. H. Adams, the
Director, makes clear the relation of this program to the
conceptions set forth to explain the origin of the earth's
physical structure. According to this view, two opposing
forces, operating through vast periods, account for the
earth's structure as we now know it. One is expressed

CARNEGIE INSTITUTION OF WASHINGTON

in differentiation, by which is meant the change of matter
from a simple to a complex state, with a corresponding
build-up of the reserves of energy. The other is the
process of assimilation, meaning the incorporation of
one rock mass into another, and representing, gener-
ally, a change towards greater uniformity or simplicity,
resulting in a corresponding degradation of form and
energy and loss of the dynamic quality possessed by the
more complex substances.

The changes in the physical world, according to this
view, may be thought of as consequences of these processes.
Moreover, the tendency in nature is for aggregations of
matter, if left to themselves, to become uniform through-
out, and, ultimately, to become completely homogeneous
in composition and texture and wholly static in respect
to energy.

Dr. Adams comments on this idea as follows :
"The significant fact is that the primary tendency for
all aggregations of matter is a degradation of form, of
energy, or of composition. Mountain masses are reduced
to peneplanes, thermal energy becomes unavailable for
useful work, and mixtures become homogeneous in com-
position and texture. But although the tendency is ever
toward the state in which individuality is destroyed, there
are intermediate stages in which the natural and usual
course of events reverses itself ; we have alternate cycles
of the twin effects that, depending on the factors to be
emphasized, may be designated as mixing and unmixing,
planation and upheaval, diffusion and segregation, de-
struction and creation, decay and growth, or assimilation
and differentiation— different names for the one set of
fundamental opposing tendencies.

REPORT OF THE PRESIDENT, 1938

" Viewed in a broad way, the problems of geophysics
are largely those of differentiation. Whether all or a
part of the Earth was once uniform in composition, it
is now decidedly heterogeneous, and differentiation is
responsible for those aspects of its geologic history that
are the most interesting and also the most puzzling. It is
easy to understand how materials can mix to form a
solution, but it is difficult to acquire adequate knowledge
concerning the mechanism by which they can unmix. A
land surface by well-known processes is reduced to a
level plane, and subsequently by forces that are not yet
well understood is uplifted to great heights. There is a
general tendency to reduce the state of all things to a dead
level, and the consequences of this tendency are simple.
The reverse effect of building up structures and differ-
ences in composition is complex and often appears to defy
explanation. In many instances we can predict the course
of processes by which structures are torn down but not
the manner in which they may be built up again.

"That part of the Earth's crust amenable to direct or
indirect observation offers a fascinating series of prob-
lems, which in common with all problems present a chal-
lenge to the inquiring mind. In accepting the challenge
we resort to laboratory experimentation and in effect
presume to imitate Nature on a small scale. At the Geo-
physical Laboratory our attack has proceeded in three
principal directions: (1) By crystallization or by other
means, we induce the separation of mixtures into their
constituents (solid, liquid, and gaseous) and define the
conditions necessary for the appearance of the individual
phases; (2) we search for mechanical processes that will
sort, transport, and arrange the products; and (3) we

CARNEGIE INSTITUTION OF WASHINGTON

study the structure of solids and liquids, utilizing the most
powerful devices of modern physics, in order to predict
the behavior of mixtures subjected to varying environ-
ment."

During the year the investigators on the Laboratory
staff have made significant progress along each of these
major lines. Important light has been thrown on the
properties of lavas, on the phenomenon of volcanism, and
on the mechanism of flowage in masses of molten silicates
through investigation of the volatile constituents of natu-
ral rocks, which has included comparison with gases aris-
ing from volcanoes. Studies of the incrustations from
volcanoes and fumaroles have shown the presence of a
surprising number of the less familiar elements, suggest-
ing that the deposition of these elements by volatile trans-
port is an important factor in the formation of iron ores.

Closely related to the work of the Geophysical Labora-
tory and, in effect, a part of its program, are the studies
of volcanic phenomena of Montserrat, one of the islands
of the Lesser Antilles, conducted by Mr. F. A. Perret, a
Research Associate of the Institution. The results of the
study will soon be issued by the Office of Publications of
the Institution as a companion volume to publications
by the same investigator on Vesuvius and Mount Pelee.

Observations of the volcanic and seismic activity on
this island have been supplemented by studies on a new
and similar phase of activity at Dominica, another of the
Lesser Antilles, located between Montserrat and Mar-
tinique. The volcanoes of the Lesser Antilles, with their
accessible peaks, continuing activity, and alternating pe-
riods of volcanic and seismic play, have afforded a valu-
able opportunity for investigation of such phenomena.

REPORT OF THE PRESIDENT, 1938

The program of the Laboratory provides for projec-
tion of this study of volcanic action to Guatemala where
preliminary examination during 1932 and 1935 disclosed
a profitable field for investigation. Funds for the purpose
are available and plans for field studies have been formu-
lated. Through cooperative effort and applying modern
physical methods, it is hoped that something of the under-
ground structure in the vicinity of an active volcano will
be learned.

The work of the Laboratory during the year also in-
cluded investigation of several mixtures containing water
as an active ingredient. Among them were : boron oxide
and water, which reveals some of the conditions in which
crystallizable substances make their appearance ; calcium
sulphate and water, study of which has solved some difficult
matters relating to the formation of gypsum deposits ; and
sodium hydroxide and water, a study marking the first
step in a program of investigations of silicate systems at
moderate temperatures and pressures. This last series
of investigations was made possible through financial aid
given by the Carnegie Corporation of New York and has,
as its specific objective, information about the formation
of the coarse crystal growths of granitic rocks known as
pegmatites and about the alteration of minerals due to
the action of heated waters.

In the Institution's Year Book for 1935-36, No. 35,
announcement was made of the development by Dr.
Charles S. Piggot, of the Geophysical Laboratory staff,
of an apparatus for obtaining core-samples of the ocean
bottom at great depths. A number of such samples are
now available and are being studied at the Laboratory

CARNEGIE INSTITUTION OF WASHINGTON

and elsewhere along with samples of the ocean floor col-
lected by dredging during voyages of the Carnegie.

TERRESTRIAL MAGNETISM

In the field of physical sciences one of the most notable
advances in the Institution's program of the past year
is marked by completion of the improved atomic physics
equipment constructed by the Department of Terrestrial
Magnetism for use in study of magnetism in its relation
to the atom. The new equipment comprises a constant-
potential generator and vacuum-tube designed to reach
potentials in excess of five million volts under precise
control. The care with which the apparatus has been de-
signed and finally realized as a completed instrument
should guarantee the greatly bettered facilities for experi-
mentation which this new tool is intended to give. The
construction of this long-planned equipment was begun
in May 1937. The equipment will greatly extend the pos-
sible scope of the Department's investigations of the
nature of magnetism and the basic structure of matter.

A second accomplished project is that of the installation
of automatic multif requency equipments at the Huancayo
(Peru) and Watheroo (Australia) Magnetic Observa-
tories for study of the magnetic conditions of the iono-
sphere. This equipment, developed at the Department,
has the following characteristics : capability of recording
accurately without interference from existing radio serv-
ices ; relatively uniform vertical radiation throughout the
frequency range ; automatic interlocking of transmitting
and receiving tuning ; mechanical simplicity and uniform
limits of precision and resolution.

With this equipment the stations at Huancayo and

REPORT OF THE PRESIDENT, 1938

Watheroo, operating continuously in conjunction with
similar equipment at the station of the National Bureau
of Standards, Meadows, Maryland, should provide a much
more nearly complete survey of the region of the upper
atmosphere than has hitherto been possible. Tests of the
apparatus at the Department's experimental station at
Kensington, Maryland, promise settlement of many vex-
ing questions as to the magnetic conditions prevailing in
the zone of the upper atmosphere.

One of the most interesting recent developments of re-
search in the Institution has arisen through cooperation
of the Geophysical Laboratory and the Department of
Terrestrial Magnetism. The long cores obtained recently
from the Atlantic sea bottom by Dr. Charles S. Piggot,
of the Geophysical Laboratory, are seen to include a great
number of layers apparently representing a record of
many thousands of years. Particles included in these
layers are found to show magnetic orientation, and the
orientation may not be the same in different parts of the
core. Similarly in sedimentary deposits of geological for-
mations there is evidence that the rocks may retain the
magnetization imparted to them by the earth's magnetic
field at the time of their deposition.

If the conditions and variations of magnetization are
finally demonstrated to represent conditions which they
seem to reflect, a method will have been developed for fol-
lowing magnetic changes through long periods at given
localities, and this makes possible a picture of earth his-
tory heretofore not attainable.

This development introduces into the study of magnetic
phenomena a distinctively new element, one which Dr.
Fleming has aptly called palaeomagnetism. The method,

CARNEGIE INSTITUTION OF WASHINGTON

in process of refinement, gives promise of becoming a
powerful new tool. By this method, it is hoped, much
will be learned concerning the magnetic history of the
earth during past geological ages.

The year has been one of unusual interest in the oppor-
tunities it has afforded for study of solar and terrestrial
relationships, and of the relations between terrestrial mag-
netism and other phenomena, such as cosmic radiation.
Since the last sunspot minimum of 1933, there has been a
steep increase in solar activity, as expressed by sunspot
numbers, reaching a value for 1937 considerably exceed-
ing any annual mean since the high sunspot maximum of
1870. Intensity of magnetic disturbance followed this
increase and the year 1937 proved to be the most active
year for over 60 years, although individual storms of out-
standing intensity did not occur until 1938.

In commenting upon the positive relationship of cosmic
radiation with magnetic and other phenomena, Dr. Flem-
ing writes :

" Worldwide decreases of 3 to 5 per cent in daily means
of cosmic-ray intensity are found to be associated with
changes in the Earth's magnetic field during two major
magnetic storms ; other magnetic storms of equal intensity
occur with no appreciable cosmic-ray effects. Thus it
appears that the entire current-system for the storm-time
field of both types of storm cannot be located at the same
distance above the Earth. A significant correlation be-
tween changes in daily means of cosmic-ray intensity for
two stations separated 50° in latitude probably results
from the mechanism responsible for the magnetic-storm
effect. Statistical analyses of the cosmic-ray records ob-
tained at Cheltenham and at Huancayo proved inadequate

REPORT OF THE PRESIDENT, 1938

to establish a sidereal diurnal variation in cosmic-ray
intensity.

" Analysis of all available data from Cheltenham, Teo-
loyucan, Christchurch, and Huancayo shows that the
major changes in the 10-day means of cosmic radiation
are all worldwide. The correlation between the worldwide
changes at different stations was found high enough to
provide important information regarding their variation
with latitude and altitude. It seems impossible to explain
the annual waves found at these stations in terms of a
solar magnetic moment."

DIVISION OF PLANT BIOLOGY

Dr. H. A. Spoehr, Chairman of the Division of Plant
Biology, reports the bringing to completion of an exten-
sive series of investigations, begun in 1922, to determine
the effect of climate in the modification of plants, and the
manner in which the latter are differentiated to meet the
complex demands of various environments. These in-
vestigations, known as transplant or varied-environment
experiments, have been carried out at a number of sta-
tions located so as to represent a range in altitude extend-
ing from sea level to the crest of the Sierra Nevada.

Although analysis of the extensive accumulation of
data has not been completed, nevertheless it has gone far
enough to indicate certain results, chief of which are:

1. Demonstration of the delicacy of balance between
the internal or gene-controlled factors and the external
environment.

2. Comprehension of the orderly complexity of species
composition in relation to plant distribution.

CARNEGIE INSTITUTION OF WASHINGTON

3. Evaluation of the capacity of plants to adjust them-
selves to different environments.

During the year two investigations dealing with the
chemistry of the photosynthetic apparatus of plants have
been brought to publication. In referring to these studies
Dr. Spoehr writes:

"The first of these concerns the leaf xanthophylls, a
group of yellow pigments contained in all chloroplasts.
Because of the fact that these substances possess a very
complicated chemical structure and because the various
members of the group differ only very slightly in struc-
ture and in their chemical properties, their isolation and
purification have been associated with many difficulties.
The isolation of these extraordinarily sensitive com-
pounds was made possible largely through the develop-
ment of special methods of chromatographic adsorption.
By this means and through the accurate determination of
the absorption spectra reliable methods have been evolved
for the characterization of this important group of natu-
rally occurring substances.

c l The other investigation referred to concerns the mech-
anism by which the plant leaf absorbs the carbon dioxide
of the atmosphere. This is the first step in the series of
chemical reactions comprising photosynthesis. The more
exact determination of the chemical system which is
involved in this first step has served to establish another
link in the series of chemical reactions comprising the
photosynthetic process.

"Photosynthesis in plants is essentially an energy-
storing chemical reaction. This energy is obtained from
the light which is absorbed by the pigments in the leaves
of the plant, and is used in reducing carbon dioxide to

REPORT OF THE PRESIDENT, 1938

a carbohydrate. The amount of energy which is required
by the plant to carry forward this chemical reaction is of
fundamental importance in establishing the chemical
mechanism which is involved in the process. During the
past year a reinvestigation of the quantum efficiency of
photosynthesis has been begun by Drs. Robert Emerson
and Charlton M. Lewis, with a view to making certain
essential amplifications of previous determinations with
improved apparatus, and with special consideration of
the physiological characteristics of the plant organisms
used."

In respect to the quantum efficiency of photosynthesis
Drs. Emerson and Lewis show that in the reduction of
carbon dioxide to carbohydrate a minimum of 112,000 cal-
ories for each unit, known as a mole, of carbon dioxide is
required. In reporting their work on this subject these
investigators say:

"In green plant photosynthesis, the energy necessary
for this process is obtained through the absorption of
visible light by chlorophyll. Photosynthesis proceeds nor-
mally in red light, where the energy obtainable from a
number of light quanta equal to the number of molecules
in a gram-mole (one mole-quantum) is only about 40,000
calories. Several light quanta must therefore be absorbed
in order to provide the minimum amount of energy re-
quired to reduce one molecule of carbon dioxide.

" According to the present concepts of physics, absorbed
light quanta cannot act additively, but only individually,
so we may suppose that each absorbed quantum effective
in photosynthesis brings about a single elementary step
in the process of carbon dioxide reduction. If three
quanta of red light were available for each molecule of

CARNEGIE INSTITUTION OF WASHINGTON

carbon dioxide, there would be 3 X 40,000 or 120,000 calo-
ries per mole, an amount greater by 8000 calories than
the theoretical minimum of 112,000. But each individual
step must require some activation energy, for which a
margin of only 8000 calories would hardly be sufficient.
Therefore it is generally believed that nothing less than
four quanta can be regarded as providing enough energy
for the reduction of one molecule of carbon dioxide to
carbohydrate."

In further summary of the work of his staff for the
year Dr. Spoehr states:

"The recent publication of the results of thirty years'
observation of changes in vegetation on the fenced lands
of the Desert Laboratory has attracted the interest of both
foreign and American workers who are dealing with
the problems of restoration and maintenance of grazing
ranges. Shorter periods of observations of the repro-
duction and growth of large desert perennials have em-
phasized the slowness of growth of individual plants and
the long periods required to bring about change in the
communities which they form.

"The close of active field work on the Sonoran Desert
project, which has been one of the principal activities
of the Desert Laboratory for the past five years, has been
followed by study of notes and collections preparatory to
publication. The work of the past year has been almost
as fruitful as the years of exploration, since it has given
time for the study of living and herbarium material and
the collection of data on climate vegetation, and the dis-
tribution of some of the most highly specialized desert
plants. The objective of these investigations has been the
determination of the origin of desert plants and their

REPORT OF THE PRESIDENT, 1938

differentiation under the impact of the severe environ-
mental conditions of the arid regions."

DIVISION OF ANIMAL BIOLOGY

Question of the geographical separation of the groups
comprising the personnel of the Division of Animal
Biology and ways of lessening the disadvantages arising
therefrom are discussed by Dr. George L. Streeter, Chair-
man of the Division. The problem which he touches upon
in connection with his own Division is likewise a problem
incident to the entire Institution organization for, in gen-
eral, groups of Institution workers are placed where their
work has naturally developed or where it can be con-
ducted to best advantage.

Thus, the Nutrition Laboratory was located at Boston ;
the Division of Historical Research with sections working
at Washington, in Yucatan, in Guatemala, and in Cam-
bridge; the Department of Embryology at Baltimore;
the Geophysical Laboratory and the Department of Ter-
restrial Magnetism at Washington, with observatories of
the latter in Peru and Australia ; the Mount Wilson Ob-
servatory at Pasadena ; the Division of Plant Biology at
Stanford University, with sections at Tucson, at Santa
Barbara, at Carmel, at Berkeley, and at Pikes Peak ; and
the Marine Biological Laboratory at Tortugas.

Were nothing done to overcome the drift, this physical
separation of the units of the organization would lead
quickly to a sense of detachment and heterogeneity with
consequent loss of Institutional efficiency. Much thought
has been given to the question of how best to overcome this
centrifugal tendency. As a partial answer has come the

CARNEGIE INSTITUTION OF WASHINGTON

Institution's program of conferences, exhibitions, lec-
tures, and interpretative statements.

Dr. Streeter's discussion of the problem as it relates
to his own Division, the units of which are located at
widely scattered points, is timely. Respecting this matter
he says:

"The activities of the component groups under the
Division of Animal Biology are reported in the following
pages and it will be seen that in general they include
related phases of physiology, anatomy, embryology, and
heredity of animals. The question repeatedly arises as
to whether it would be desirable to bring these researches
all under one roof, so to speak, or at least in one locality.
Much might be gained by a closer assembly, but it would
also involve some sacrifices.

"Even were such a concentration feasible, careful con-
sideration should be given to all the factors concerned.
The present arrangement has been one of natural evolu-
tion. The various projects have sprung up where it was
thought they could be best conducted ; some in large scien-
tific centers, others in isolated locations where environ-
ments of a special character were demanded by the nature
of the project.

"As far as possible, the disadvantage of the dispersion
of the research personnel has been counteracted by fre-
quent conferences and exchange of facilities between the
individuals of the different groups. As a consequence,
it is more and more being found that a community of
interest and cooperative endeavor are of mutual advan-
tage and an added source of strength. Inasmuch as the
selection and grouping of the researches have been of an
evolutionary or empirical nature it is to be expected that

REPORT OF THE PRESIDENT, 1938

their goals and planning will be subject to change and
adjustment from time to time.

" Projects are dropped as they reach a reasonable com-
pletion and attention is turned in other directions. Trial
and error are dominant features in the organization of
the groups and subgroups just as they are in their re-
searches and as they are in nature. The investigator is
on the fringe of the unknown where in his uncertain ad-
vances he must be alert to advantageous alterations in
course. He must have a plan but his plan must not
commit him to a program that cannot be terminated when
it becomes barren."

Since October 1936 the Eugenics Record Office of the
Institution, under direction of Dr. H. H. Laughlin, Assist-
ant Director of the Department of Genetics, has been
collaborating with the State of Connecticut in a survey
of the human resources of that commonwealth. The Gov-
ernor of the State appointed a commission with Frederic
C. Walcott as chairman.

The Governor duly instructed this commission to make
a thorough survey of the human resources, good and bad,
of the State of Connecticut, and particularly to investigate
the source, the apparently increasing supply, and the
racial, moral, and economic costs of those human inade-
quates who finally either directly or indirectly become
economic charges or moral debits of the state, the county,
or the town.

The commission, in turn, appointed Dr. Laughlin direc-
tor of the survey. An office and exhibit room were duly
opened in the State Office Building at Hartford, and an
office and field staff began work.

Early in 1938 the collection of the data was completed

CARNEGIE INSTITUTION OF WASHINGTON

and analysis of the returns and preparation of the sur-
vey's report begun, of which the complete material has
now been laid before the commission. This general report
covers such researches as the following :

1. Analysis of the laws of Connecticut in direct refer-
ence to the human resources of the State.

2. Assemblage of data on the inadequate and handi-
capped residents of each of the 169 towns of Connecticut.

3. Special consideration of the problem of the feeble-
minded in Connecticut, comprising a study of nearly
12,000 persons in respect to important qualities or factors.

4. A study of the 661 inmates of the Connecticut State
Prison for Men at Wethersfield.

5. The direct cost to the people of the State for the care,
training, and treatment of the defective, dependent, de-
linquent, and handicapped classes.

In respect to this last study the findings show the
astonishing facts that in 1937 the people of Connecti-
cut, through their State government, were expending
more per capita for the handicapped classes than the
State government was expending for all purposes twenty
years ago ; also, that at the present rate every inhabitant
of Connecticut is expending, through the State govern-
ment, five and one-third times as many dollars per year on
these groups as the average inhabitant was spending
for the same purpose twenty years ago.

In the field of embryology Dr. Streeter states that the
year has brought notable success, in that the effort to
obtain younger mammalian ova that are assuredly dated
has extended the known field another twenty-four hours.
In 1934 he reported having obtained a 10-day macaque
embryo, whereby observational knowledge of the mechan-

REPORT OF THE PRESIDENT, 1938

ism of development was extended into the twenty-four
hour period preceding any then known primate ovum.

The year following he was able to report two 9-day speci-
mens, one just before implantation and one in process of
attachment to the uterine wall. This year the finding of
an 8-day primate ovum has given the investigators ma-
terial from which much can be learned about the first and
most fundamental chapter in development of the body
tissues of the mammalian organism. In describing this
8-day ovum of the macaque monkey and telling of its im-
portance Dr. Streeter writes :

"An outstanding feature of it is the fact that at the
embryonic pole there are still a few cells that are approxi-
mately double the size of the others. It is clear to see that
they have not divided so many times. These relatively
inactive cells appear to be the ones that are destined to
form the embryo proper. They are large, few in number,
not oriented in position, and show no tendency to unite
into a common structure, all of which are characteristic
of primitive blastomeres.

"In contrast to these primordial cells, the other cells
are numerous, small, and are rapidly differentiating into
special structures which will serve to attach the ovum to
the uterus and eventually provide the contained embryo
with its nourishment and other physiological require-
ments. In the point of sequence the stage is set before
the embryo makes its appearance.

"In this blastocyst Dr. Heuser finds that he can see
clearly that the materials of the ovum have, already on
the eighth day, been segregated into the embryonic and
extra-embryonic, or auxiliary, parts of the ovum. Thus
the eighth day may be said to mark the completion of the

CARNEGIE INSTITUTION OF WASHINGTON

first and hence the most fundamental chapter in the devel-
opment of the ovum."

In the parallel effort to push further back toward the
beginnings of the human organism Dr. Streeter reports
opportunity of studying a 15-day old presomite specimen
at the Anatomical Laboratory of the University of Chi-
cago. This specimen he says is certainly normal, is in a
good state of preservation, and is destined to take its
place as a standard of orientation in the procession of
stages through which the human embryo passes in its
development. A slightly younger specimen, known as the
Yale Embryo, probably between 13 and 14 days old, has
also been subjected to careful study as has a third human
embryo, younger still than either of the others.

A review by Dr. W. H. Lewis of his studies on the
cultivation and cytology of cancer cells, an investigation
that has extended over a period of some years, confirms
his previously expressed opinion that cancer cells are
permanently altered cells. That is to say, they constitute
new types that are derived from normal and usually
healthy cells, which have been permanently altered by
environmental influences or various other agencies. After
the normal cells have undergone the initial alteration into
malignant cells, he says, the special environmental influ-
ences or agents which produced them are not necessary for
the maintenance of their peculiarities.

Dr. Lewis finds that in tissue cultures the malignant
cells are visibly different from normal ones and from each
other. They retain their peculiar characteristics from
one generation to another when serially transplanted from
animal to animal and for months or even years. From six
of the tumors malignant cells were cultivated "in glass"

REPORT OF THE PRESIDENT, 1938

for two to over four years. In that way pure colonies of
the malignant cells were obtained which retained both
their cultural characteristics and their malignancy. When
inoculated into animals typical tumors resulted. From
these, in turn, pure colonies of characteristic malignant
cells were secured and these also produced typical tumors.

Last year Dr. A. F. Blakeslee, Director of the Depart-
ment of Genetics, reported the discovery that treatment
of the seeds of Datura ( Jimson weed) with the alkaloid
colchicine would bring about changes in structure of the
seedlings which were interpreted as due to doubling the
number of those minute elements known as chromosomes.
It was pointed out that if the interpretation were correct
and the methods could be used with other forms, a tool
of considerable value would be available both to the prac-
tical plant breeder and to the plant geneticist interested
in problems of evolution. Dr. Blakeslee reports that the
present year's work has shown that induction of chromo-
some doubling by chemical treatment is of wide applica-
tion among flowering plants and enables the investigator
of certain problems to work with a measure of precision
not hitherto possible.

Soaking seeds in solutions of colchicine of different
concentrations for different species is the most convenient
method of treatment. Seeds of Portulaca respond to the
concentration of 0.0002 per cent for two days by producing
seedlings with swollen stems. Seed treatment with 0.4
and 0.8 per cent solutions for 4 to 8 days has been found
well adapted to Datura and induces an abundant produc-
tion of 4:n branches.

The effect of the drug is first noted in delaying germina-
tion and development. When the treatment is severe the

CARNEGIE INSTITUTION OF WASHINGTON

stems of the seedlings are strongly swollen and many fail
to develop beyond the cotyledon stage. The leaves of af-
fected plants are characteristically roughened owing to
the fact that they contain a mixture of 2n and 4w cells.
From these "mixochimeras" there ultimately may grow
out branches with smooth leaves which either are normal
2n or contain twice the normal number of chromosomes
and are therefore 4w. The 4w flowers may be recognized
by the larger size of their pollen grains or by the more
tedious method of actually counting the chromosomes in
young buds which have been fixed and stained by the
acetocarmine method.

In addition to the seeds, vegetative parts of the plant
may be treated by a variety of methods. The most suc-
cessful method consists in spraying growing points with
solutions or better with emulsions containing colchicine.
On the other hand it was found that injecting solutions
and allowing solutions to be soaked up through the cut
parts of the stem were not successful.

One of the early problems in the use of colchicine was
the extent to which this drug would be effective in doub-
ling the chromosome number of other forms than Datura.
A number of species were selected for testing because of
their adaptability to experimental cultivation or because
of their relation to special problems.

The species successfully treated represent a consider-
able number of genera and families, enough to indicate
that the method is of wide application. In addition, a
number of forms which showed the vegetative peculiari-
ties characteristic of tissue with doubled chromosome
number following colchicine treatment were discarded
for various reasons before the special treatment required

REPORT OF THE PRESIDENT, 1938

to force out \n branches had been developed. This was
notably true of the grass family, but other investigators
who have specialized on this family have recently been
successful in securing 4w races of grasses through treat-
ment with colchicine. The fungi seem highly resistant to
the toxic action of colchicine.

Interesting attempts were made to double the chromo-
some number in animals through employment of the col-
chicine method. Trout eggs were used in the hope that
through treatment the fusion nucleus could be induced
to double its chromosomes before the first division.

In all the experiments, however, difficulty was encoun-
tered in getting the drug to penetrate the membranes and
so, in consequence, the efforts were unsuccessful. It is
thought possible that eggs which develop outside the body
are better protected against unfavorable environmental
influences than those which develop within the body. In
consequence the latter might be more promising material
in which to attempt chromosome doubling despite the
technical difficulties involved in handling the eggs of such
species.

Dr. Oscar Riddle and his associates in study of the
endocrine system report that it has now become clear that
the pituitary gland is largely responsible for the regula-
tion, adjustment, and coordination of this system and
for certain other activities of body and mind besides.
It would now seem possible, they assert, to conclude that
in higher animals and man the brain and the pituitary
gland are the two prime sources from which the activities
of an individual are derived.

The investigations reported here, like those of past
years, present parts of an effort to learn those endocrine

CARNEGIE INSTITUTION OF WASHINGTON

agencies and mechanisms which condition or control func-
tions such as growth (development), reproduction, and
regulation in the bodies of higher animals and man. Much
of the experience of the year points to the unpredicta-
bility of relationships among hormones ; and perhaps the
most notable thing observed is the extent to which one
hormone may either increase (synergize) or decrease the
specific action of another. These studies of Dr. Riddle
and his associates have been greatly aided by a grant from
the Carnegie Corporation of New York to the Carnegie
Institution of Washington.

On November 1, 1937, Dr. Francis Gr. Benedict, Direc-
tor of the Institution's Nutrition Laboratory since its
establishment in 1908, retired. Since Dr. Benedict's re-
tirement the work of the Laboratory has gone forward
under supervision of Dr. Thorne M. Carpenter, the Act-
ing Director.

Dr. Carpenter reports that the early part of the year
was occupied, for the most part, in an intensive effort to
complete the preparation for publication of monographs
and journal articles by Dr. Francis G. Benedict before his
retirement as Director. This was most successfully ac-
complished, and the several publications have gone
through the press.

The experimental work for the year has continued
largely in the same fields of research as have already been
in progress. In spite of considerable observation on the
biological variations in basal metabolism, there are still
gaps in the data and excellent leads for future study, par-
ticularly of those animal species in which there are large
variations in size and configuration.

Dr. Carpenter states further that there is at present a

REPORT OF THE PRESIDENT, 1938

renewed interest in bodily heat regulation, as evidenced
by the number of recent publications concerned with the
distribution of heat elimination, the skin and the body
temperature. The present increasing use of methods of
air conditioning, particularly air cooling (some of which
are far from satisfactory either from the physiological
standpoint or from the standpoint of comfort), indicates
the need of more knowledge of human heat regulation in
response to rapid and unusual changes in environmental
conditions. The past experience of the Nutrition Labora-
tory in the studies of skin and body temperatures and its
experimental equipment, particularly the emission calori-
meter for humans, provide conditions for a comparative
study of heat production and heat elimination which
would be of value in understanding the physiological proc-
esses of the body when there is a necessity for rapid adap-
tation to changes in environmental conditions.

DIVISION OF HISTORICAL RESEARCH

The staff of Historical Research has devoted the year
largely to organizing accumulated data and to the writing
of reports, it being the policy of the Division not to under-
take new researches until record has been made of earlier
activities. This has served to focus special attention upon
problems of publication. Respecting this matter the
chairman of the division, Dr. A. V. Kidder, makes the
following observations :

"In general, first class factual literature in the social
sciences and the humanities is pitifully scanty. In these,
as in the natural sciences, the collection and the setting
forth of data must precede synthesis and the drawing of
conclusions. And because of the bewilderingly faceted

CARNEGIE INSTITUTION OF WASHINGTON

life of man and the infinitely wide range of man's doings
throughout the ages, in every conceivable type of histor-
ical setting, and in all possible sorts of physical environ-
ments, the human record must, for the present at least,
be largely descriptive.

" Expression by formula is not feasible, nor can there
often be used the condensed forms appropriate for expo-
sition of the regularly repeating phenomena of biology.
Publication, therefore, even in the case of the relatively
small group of studies with which the Division is occu-
pied, is inevitably voluminous ; archaeological papers must
carry a great amount of illustration.

' ' Costs, accordingly, are bound to be heavy; but, on the
other hand, it is only fair to point out that acquisition of
most anthropological and historical materials is relatively
inexpensive, there being little or no call for physical equip-
ment, for laboratories or instruments. However, neither
need for much publication nor cheapness of fact finding
justifies waste. Also, from the point of view of utility,
it is essential that results be thoroughly digested and
succinctly stated.

" Because of the vast increase in scientific writing of
all sorts, as well as because of the rapidly mounting costs
of printing, it is certain that present methods for dissemi-
nation of knowledge will have to be rather drastically
overhauled, those of the disciplines concerning man per-
haps most severely of all. How this may be brought about,
in the case of its own product, is being given anxious con-
sideration by the Division. Those of its reports which are
now well along in preparation will be submitted in forms
sanctioned by previous practice. But it is probable that
current studies of the situation will result in recommen-

REPORT OF THE PRESIDENT, 1938

dations looking towards much simplified presentations
and considerable reduction in manufacturing costs."

In pursuance of the policy of making suitable record,
from time to time, of investigations finished or well ad-
vanced, Dr. Kidder reports completion of two outstanding
studies made by members of the section of Aboriginal
American History. One of these is a compendious mono-
graph of five quarto volumes representing the fruits of
the twenty years of study which Dr. Sylvanus G. Morley
has devoted to the hieroglyphic inscriptions found in the
ruined Maya cities of the Department of Peten, Guate-
mala. The other is by Mr. Earl H. Morris, who has spent
an equally long time in studying the very important Bas-
ket Maker and Pueblo sites of northern New Mexico and
adjacent regions. These two monographs, the one now
in press, and the other being prepared for the press, will
rank as fundamentally significant contributions to the
literature of their respective fields.

After eleven seasons spent in excavation work at Uaxac-
tun, in the Department of Peten, Guatemala, presumably
the oldest known of the First Empire cities of the Maya,
activities were brought to an end in 1937. The findings of
the first years as reported by Dr. and Mrs. Oliver G.
Ricketson have recently been published by the Institution.
Work at this site during the last six years was largely
devoted to study of the so-called " Palace," a multi-cham-
bered structure which grew by accretion through a long
period, and where thorough study by Mr. A. L. Smith
has yielded very valuable data upon architectural devel-
opment and the succession of pottery types. Mr. Smith
and his associates in study of the "Palace" are engaged
in preparing the final report upon the general archaeology

CARNEGIE INSTITUTION OF WASHINGTON

of the sites and upon results of the study that is being
given the enormous collections of ceramic material that
were made at Uaxactun.

Dr. Kidder also reports termination of work on the
mounds and tombs of Kaminal-juyu, near Guatemala
City, a project to which he has given his personal atten-
tion. The collections which he obtained at the site, par-
ticularly those of pottery, throw much light upon the
chronological relations between the cultures of the Guate-
mala highlands, of the Maya First Empire in Peten, and
those of central Mexico. Through collapse of the roofs
of the tombs, the mortuary pottery was found to have
been badly crushed and broken, in consequence of which
the task of repairing the more than two hundred vessels,
many of great beauty, and of types hitherto unknown, has
been one of great difficulty. The work of repair is going
forward steadily, each completed piece is photographed,
artists are reproducing the particularly fine pieces in
black and white or in water color, and ultimately all the
pieces will be placed in the National Museum at Guate-
mala for permanent exhibition.

As to the activities of the staff group working in post-
Columbian American history Dr. Leo F. Stock spent the
summer in England in gathering material for the fifth and
last volume of the series, Proceedings and debates of the
British Parliament respecting North America. This series
when completed will contain all the contemporary records
that can be found, in print or in manuscript, of what was
done and said in the parliaments of England, Scotland,
and Ireland concerning North America, from the first
mention of that continent to the conclusion of peace and
acknowledgment of American Independence in 1783.

REPORT OF THE PRESIDENT, 1938

In January of 1938 the Institution brought out the
third and last volume of the series, Historical documents
relating to New Mexico, Nueva Viscaya, and approaches
thereto, to 1773. These volumes contain texts and trans-
lations of a large number of documents, hitherto unknown
to historical scholars, which were found by the late Dr.
Bandelier and Mrs. Bandelier in the Archivo General de
Indias in Seville and elsewhere. The documents present
a wide variety of material, illustrating all portions of the
history of the Rio Grande region from the first explora-
tion of it by the Spaniards.

Although the monumental series of eight volumes en-
titled Letters of members of the Continental Congress
was completed by Dr. E. C. Burnett in 1936, since that
time he has been at work upon an interpretative volume
which is based primarily upon the published series. The
series contains practically all the contemporaneous evi-
dence that could be found bearing upon the discussions
arising in the Congress. Much of it consists of letters
which members wrote from day to day, from the seat of
the sessions, to the governors or other authorities of their
states, or to relatives and friends. Arranged in chrono-
logical order, these letters and extracts by various mem-
bers, from different states, cast a flood of light upon the
transactions of the Congress throughout fifteen momen-
tous years.

In the effort to bridge the gap between the present and
the pre-Columbian past through study of the documentary
history of the Peninsula, there has been included in the
Maya program the accounts of the conquerors and early
ecclesiastics regarding the aboriginal condition of the
Maya.

CARNEGIE INSTITUTION OF WASHINGTON

Dr. Kidder comments on certain aspects of the History
of Yucatan project as follows:

"At the present time it has seemed desirable to inquire
more closely into what the white man found when he
arrived in the various parts of the Maya area ; the state
of affairs at the time of this contact, as distinguished from
subsequent developments influenced by European culture,
on one hand, and previous conditions no longer existing
but disclosed by archaeological investigation, on the other.

"There are some indications that more or less similar
conditions may well have existed for at least three cen-
turies prior to the Conquest in the highlands of Guate-
mala and perhaps considerably longer in regions between
that area and the state of Yucatan. In Yucatan, however,
there was a great political and social revolution about the
middle of the fifteenth century. Its more conspicuous
effects were the breaking up of a centralized government
and the abandonment of the stone-vaulted buildings,
which were replaced by more or less perishable structures
with thatched roofs. In the Old World such a decline in
architecture has been either more gradual or the result
of invasion and immigration by less cultured peoples,
which was not the case in Yucatan at this time. Much of
the previous state of affairs, which reminds us in some
respects of the conditions in the highlands of Guatemala
at the time of the Conquest, was still a matter of general
knowledge when the Spaniards conquered Yucatan, so
it may be possible to trace the causes and effects of this
famous crisis in aboriginal American history."

In work of the Section on History of Science, during
the year, Dr. George Sarton has made excellent progress
in preparation of the third volume of his monumental

REPORT OF THE PRESIDENT, 1938

series, The Introduction to the History of Science, In
this work Dr. Sarton has had the help of Dr. Alexander
Pogo who, while assisting Dr. Sarton, has continued his
astronomical studies bearing on the problem of the corre-
lation of Maya and Christian chronologies.

Study of the history of Greek thought has been dili-
gently prosecuted by Dr. W. A. Heidel, who throughout
the year has been chiefly occupied with the history of
Greek mathematics down to 400 B. C, or rather with the
attempts made by various modern scholars to describe the
development from data that are exceedingly meager.

ST. AUGUSTINE AND MONTEREY RESEARCH

PROJECTS

Cooperative studies in history of two early American
cities arising out of Spanish culture have been carried on
at St. Augustine, Florida, and Monterey, California.
While these activities have arisen independently, in cer-
tain respects they are intimately related, since both con-
cern study of Spanish influence upon the United States
and express in some measure a connection with activities
of the Institution in contiguous areas of Latin America.

The program of work at Monterey had been carried on
by investigators in California for a number of years, much
having been accomplished in preservation of historic sites
and in study of valuable materials. The Institution has
cooperated so far as possible in preserving the Monterey
Custom House, one of the most important sites, and has
continued its interest by supporting activities of Mr.
Emerson Knight and Dr. Aubrey Neasham in study of the
plan of the city with reference to history of outstanding
monuments and materials. Extraordinarily fine coopera-

CARNEGIE INSTITUTION OF WASHINGTON

tion of the citizens of Monterey, and their activity in pro-
tection of things of historical value, give reason to believe
that there is developing at that place one of the most im-
portant opportunities for study of the Spanish influence
upon the United States. A general plan of the city, now
being developed through cooperation of the principal
agencies related to the government of Monterey, has pro-
duced a picture of what may be done with the city, and
marks definite progress in development of the area.

Study on the St. Augustine research project, concern-
ing which a statement appeared in the annual report of
1937, has advanced rapidly in the past year, with emphasis
upon those features which give evidence of furnishing the
outlines of a picture covering the story of this, the oldest
city of the United States, from the date of its founding up
to the present time. Determination to center investiga-
tion upon a report covering development of the defense
system of St. Augustine, and its relation to the frontier of
Florida, has made it possible to concentrate information
from many sources in an extremely interesting report by
Verne E. Chatelain on "The Florida Frontier and Its
Defenses, 1565-1785." This work has been completed for
publication, and will contribute in a very definite way to
development of a program for interpretation of this very
striking story involving contacts with Spain, France, and
England, on the southern border of what is now the United
States.

The investigations in this problem of the defenses and
the Florida frontier from 1565 mark an important ad-
vance in study of the area, and they are intimately con-
nected also with other investigations which have to do
with the broader story of the region reaching into the

REPORT OF THE PRESIDENT, 1938

interpretation of economic and governmental problems.
In other directions the researches extend into the field of
general archaeology of southeastern United States, and it
is hoped that ultimately the complete story of human oc-
cupation of this region may be made available.

Cooperation of the citizens of St. Augustine in these
studies has included not only aid in furtherance of the his-
torical and general scientific researches, but has involved
as well the preparation of a general plan for development
of this region. This project looks toward a zoning pro-
gram in which the things of major value historically may
retain their scientific and historical significance, and at
the same time fit into a general aesthetic scheme making
for the most acceptable living conditions in the city and
its immediate environment.

EARLY STAGES OF HUMAN HISTORY

In the earlier reaches of history as relating to man,
there has been continued progress during the past year on
many problems of unusual interest. The studies of Dr.
H. deTerra on early man in Asia were extended from
India to southeastern Asia and then to Java. Cooperation
of Dr. P. Teilhard du Chardin in conduct of these investi-
gations gave opportunity to bring into this program of
study the combined data and experience from researches
in India and China and to apply all available information
to the program planned for the southeastern region.

In his visit to Java Dr. deTerra had the cooperation of
Dr. G. H. E. von Koenigswald, who has contributed so
largely to knowledge of the Pithecanthropus problem.
Review of the Pithecanthropus region of Java by these
investigators has given a more extensive and a clearer

CARNEGIE INSTITUTION OF WASHINGTON

picture of the geology and palaeontology of the region
than has hitherto been available.

In extension of his researches of last year in Java Dr.
von Koenigswald was successful in obtaining additional
Pithecanthropus material, giving important skull char-
acters. The recent find throws still further light on the
structure, stage of evolution, and relationships of this
most interesting creature.

In America study of early man was extended by Dr.
L. S. Cressman, of the University of Oregon, who has con-
tinued to discover new cave sites in eastern Oregon con-
taining remains of early man, who seems to have lived
there near the time of beginning occupation of that region.
In several caverns volcanic ash or pumice occurs above
deposits containing human relics. In the Paisley Cave
this ash seems, according to Dr. Howel Williams, to have
come from eruption of Mount Mazama, which occupied
the site of Crater Lake to the south.

Contribution of new information from Clear Lake, Cali-
fornia, by Mr. M. R. Harrington, furnishes a record of
unusual interest and promise, with human relics appar-
ently of great age. Excavations by Mr. Malcolm Rogers,
of the San Diego Museum, have given a story of deposits
of much significance, and with the record of a culture that
promises important advance in knowledge of the earlier
stages in America.

Dr. B. Antevs has continued his critical studies on
climate in relation to early man. His researches have
furnished some of the most important evidence available
on relation of the history of early man to climatic changes,
and to evolution of life that was associated with ancient
man in America.

REPORT OF THE PRESIDENT, 1938

HISTORY EXPRESSED THROUGH GEOLOGY

Extension of history into the earliest available records
has carried investigators cooperating with the Institution
into sections of the Grand Canyon where some of the be-
ginnings of our earth story are recorded. Mr. Edwin D.
McKee has shown relation in structure between ancient
formations of the Grand Canyon and recent deposits of
the Colorado Delta, and in connection with his studies has
published an important work on the rocks of the upper
Canyon wall.

Dr. N. E. A. Hinds has continued his extraordinarily
interesting work on the series of Grand Canyon forma-
tions just below the level where a satisfactory record of
life begins.

The expedition carried through the Grand Canyon by
Dr. Ian Campbell and Dr. John H. Maxson, of California
Institute of Technology, late in 1937, obtained new and
important data in the oldest part of the known record,
where the original structure of the rocks has been al-
tered by processes which in the hands of time bring great
changes. The results of this study throw new light on
one of the most interesting chapters of earth history.

OBITUARIES

The death of Dr. William Wallace Campbell on June
fourteenth, 1938, removed from the group of Trustees of
Carnegie Institution one who had shown
WllCamPTeiiIace himself exceptionally competent and effec-
tive both as a member of the administra-
tive board and as adviser and counselor in practically the
whole range of scientific and human problems which the
Institution encounters. Dr. Campbell was especially

CARNEGIE INSTITUTION OF WASHINGTON

fitted for service on the Board of Trustees of the Institu-
tion by his long and distinguished career as an investi-
gator in astronomy, his administration of Lick Observa-
tory, his service as President of the University of Cali-
fornia, his wide experience in administration of great
scientific organizations, such as, the National Academy
of Sciences and the American Association for the Advance-
ment of Science, and above all by his broad and deep
interest in the types of problems which the Institution
might be expected to meet.

After his election to membership on the Board of Trus-
tees in 1929 Dr. Campbell was present at all meetings
excepting those for which attendance was impossible by
reason of illness. On every occasion when it was possible
to give service, he was ready and eager to aid in study of
critical questions confronting us. The measure of his
interest and understanding of the Institution seemed
almost to rank with that of the persons who were inti-
mately acquainted with the ideals and purposes of the
Founder. There may be no doubt concerning the great in-
fluence of his advice and judgment in advancement of
the Institution program along the best lines open dur-
ing the period in which he served as a member of the
Board of Trustees.

Through the period of his connection with the Carnegie
Institution, beginning in 1905, and extending to the date of

his death on February twenty-second Dr.
GeorHaiellery Hale devoted to the problems of astronomy

which he developed at Mount Wilson a type
of interest and attention rarely found in any investigator.
His exceptional talent and wisdom applied through Mount

REPORT OF THE PRESIDENT, 1938

Wilson Observatory made a contribution which marks an
epoch in astronomical research. In addition to the record
made by specific researches, and in his fine administration
of Mount Wilson Observatory, Dr. Hale performed a
service of great importance to the Institution and to sci-
ence through the influence of his example in advancing
standards of thought and work. To an unusual degree
Dr. Hale illustrated the significance of leadership in an
organization. It is interesting to note also that the great
research project built around the specific program of
Mount Wilson Observatory extended an influence in all
directions, ranging from the effect upon developing insti-
tutions devoted to science and education as at California
Institute, to education regarding the practical significance
of fundamental physics as applied in great industries de-
pending often for their ultimate development upon ad-
vances in basic physics.

Among the many and varied types of institutions de-
voted to astronomical research, Mount Wilson Observa-
tory and its associated activities constitute an outstanding
result of the creative interest and activity of Dr. Hale.
Initiated originally for the purpose of natural and proper
concentration of attention upon the nearest star, namely,
the sun, the investigations extended themselves in every
direction through the universe, carrying the data obtained
from the sun to interpretation of other stars, and on into
the outer fields of nebulae and problems of the universe.
Back again to the sun, these lines of thought turned to in-
terpret more fully the solar problem, in some measure in
terms of what was learned through study of other stars.
So the work of Dr. Hale contributed powerfully both to
stimulation of the most intensive type of research on par-
es

CARNEGIE INSTITUTION OF WASHINGTON

ticular problems, and to development of those broader
principles which underlie our understanding of the nature
and structure of the universe.

Development of astronomy by adaptation of methods
devised and carried out by Dr. Hale will continue through
the ages. Though the means utilized for furtherance of
research may change quickly to types apparently little
related to those now in use, there can be no dimming of
the influence that Dr. Hale's work at Mount Wilson will
continue to exert upon astronomical and physical research
of future epochs.

BUDGET OF 1939

Corresponding to the situation generally in organiza-
tions largely dependent upon income from securities,
preparation of a budget program from 1939 has presented
difficult problems, at least to the extent of estimates af-
fected by shrinkage of income below that of 1938. Careful
handling of investments by the Finance Committee and
the Investment Office has, however, developed a situation
which is relatively less difficult than seems to appear in
many agencies with comparable problems.

Fortunately, the generally unsettled conditions in the
field of investment and finance made clear before the
beginning of the past year the desirability of planning
for such adjustments as would make possible in 1939 a
continuation of the Institution's program without serious
dislocations. The carrying over through 1938 of unal-
lotted funds gave a considerable sum to be added to normal
income. Care in handling of expenditures during the past
year permitted retaining of a Contingent Fund of such
size that an important contribution could be placed in

REPORT OF THE PRESIDENT, 1938

the Income Account for 1939, and still leave for the re-
mainder of this year a Contingent Fund adequate to pro-
tect the present budget.

REPORTS ON INVESTIGATIONS

DIVISION OF ANIMAL BIOLOGY

George L. Streeter, Chairman

The activities of the component groups under the Division of Animal
Biology are reported in the following pages and it will be seen that in
general they include related phases of physiology, anatomy, embryology,
and heredity of animals. The question repeatedly arises as to whether
it would be desirable to bring these researches all under one roof, so to
speak, or at least in one locality. Much might be gained by a closer as-
sembly, but it would also involve some sacrifices. Even were such a
concentration feasible, careful consideration should be given to all the
factors concerned. The present arrangement has been one of natural evolu-
tion. The various projects have sprung up where it was thought they
could be best conducted; some in large scientific centers, others in isolated
locations where environments of a special character were demanded by the
nature of the project.

As far as possible, the disadvantage of the dispersion of the research
personnel has been counteracted by frequent conferences and exchange of
facilities between the individuals of the different groups. As a consequence,
it is more and more being found that a community of interest and coopera-
tive endeavor are of mutual advantage and an added source of strength.
Inasmuch as the selection and grouping of the researches have been of an
evolutionary or empirical nature it is to be expected that their goals and
planning will be subject to change and adjustment from time to time.
Projects are dropped as they reach a reasonable completion and attention
is turned in other directions. Trial and error are dominant features in the
organization of the groups and subgroups just as they are in their researches
and as they are in nature. The investigator is on the fringe of the un-
known where in his uncertain advances he must be alert to advantageous
alterations in course. He must have a plan but his plan must not commit
him to a program that cannot be terminated when it becomes barren.

One of the projects that were brought to a conclusion during the past
year is the survey of the human resources of Connecticut. This was under-
taken as a cooperative study by a commission appointed by the governor
of the state of Connecticut and the staff of our Eugenics Record Office.
The survey was of importance to the state because of the alarming and
increasing expenditures necessary for the care and treatment of its socially
inadequate classes. It was of interest to the staff of the Eugenics Record
Office because such a survey fell directly in the field of eugenic and popula-
tion studies with which they were especially equipped to deal. Now after
two years of concentrated effort the factual data, covering the biological
and eugenical aspects of the problem, have been collected, classified, and
analyzed and placed at the disposal of the Commission. It is realized that
the biological point of view, though a very important one, is but one aspect
of this population problem and it happens to be the one to which our facili-
ties are limited.

4 CARNEGIE INSTITUTION OF WASHINGTON

DEPARTMENT OF EMBRYOLOGY 1

George L. Streeter, Director

EARLY STAGES OF THE PRIMATE EMBRYO

The Eight-Day Primate Egg

In Year Book No. 33 a report was given of the obtaining of a 10-day
macaque embryo and it was pointed out that our vision of the mechanism
of development was thereby extended into the 24-hour period preceding any
hitherto known primate ovum. The year following we were able to report two
9-day specimens, one just before implantation and one just in the process of
attaching. With these two eggs the known territory was extended another
24 hours earlier. During the past year we have obtained an 8-day ovum
and again a still earlier 24 hours has been mastered. This carries us back
to where, in its histological structure, the primate ovum is close kin to other
mammalian forms, and to where they have in common the developmental
pattern of a blastocyst. It is of the greatest importance that we have ac-
quaintance with this expression of their common unity in functional require-
ments and the common way they have of meeting them. In going back to
origins, once this unity is arrived at, any of the earlier developmental phe-
nomena are in large part common to all mammals and we can in those early
periods study them in any order, genus, or species that suits our convenience.

The 8-day ovum of the macaque consists of a blastocyst having a diameter
of 0.175 mm., still enclosed by a disintegrating zona pellucida. This unique
specimen was reported upon by Dr. C. H. Heuser before the American Asso-
ciation of Anatomists. An outstanding feature of it is the fact that at the
embryonic pole there are still a few cells that are approximately double the
size of the others. It is clear to see that they have not divided so many
times. These relatively inactive cells appear to be the ones that are destined
to form the embryo proper. They are large, few in number, not oriented in
position, and show no tendency to unite into a common structure, all of
which are characteristic of primitive blastomeres. In contrast to these pri-
mordial cells, the other cells are numerous, small, and are rapidly differenti-
ating into special structures which will serve to attach the ovum to the uterus
and eventually provide the contained embryo with its nourishment and
other physiological requirements. In the point of sequence the stage is set
before the embryo makes its appearance. In this blastocyst Dr. Heuser
finds that he can see clearly that the materials of the ovum have, already
on the eighth day, been segregated into the embryonic and extra-embryonic,
or auxiliary, parts of the ovum. Thus the eighth day may be said to mark
the completion of the first and hence the most fundamental chapter in the
development of the ovum.

Implantation

The second chapter in the history of the ovum is its attachment and im-
plantation in the endometrium of the uterus. But this is a long and com-
plicated process overlapping the subsequent stages and so is not exactly a

1 Address: Wolfe and Madison Streets, Baltimore, Maryland.

DIVISION OF ANIMAL BIOLOGY 5

chapter. Implantation must begin, however, and establish its initial prin-
ciples before growth and development of the ovum can ensue. Some phases
of this process have been described in previous reports. During the past
year a study of placentation in the macaque has been brought to a conclu-
sion by the author in cooperation with Dr. G. B. Wislocki and published
in its completed form. The study is based on a series of stages representing
an almost day by day record from the ninth day when the egg first fastens,
through the early and formerly least-known phases of placental develop-
ment, up to the 35th day, by which time the mature features of the placenta
are attained. In fact this constitutes the only relatively complete record
in existence of the development of this fetal structure in any primate. The
earlier stages are quite unknown in the gibbon and the anthropoid apes and
in man our knowledge is fragmentary concerning all events preceding the
14th day.

From the biological standpoint the phenomenon of implantation is of
peculiar interest. Here we have the ovum as a minute living organism
attaching itself to the surface epithelium of the uterus and, after inducing
both stimulative and degenerative changes in it, we see the ovum ingest this
altered epithelium, with a corresponding increase in its own mass. The
whole picture of this act of parasitism can be followed in its finer cytological
details and one can determine the microscopic characteristics of the sur-
render of one living tissue to another. During the first two weeks this in-
gestion of maternal cells and intercellular plasma provides the sole source
of growth material for the embryo and for a long time it overlaps the
materno-fetal vascular exchange which, to a large extent, gradually re-
places it.

The placental development is found to pass through three general periods
or stages. The first of these is the prelacunar stage, in which trophoblast cells
of the ovum erode and ingest the maternal epithelium at the implantation site
and thus come in direct contact with the uterine stroma. While this is
happening the maternal epithelium of the surrounding area proliferates,
thereby building more pabulum for the trophoblast cells to fatten on. Within
24 hours a thick trophoblastic plate is formed at the embryonic pole of the
ovum, sealing in the gap created by the disappearance of the maternal
epithelium.

A second stage follows during which the trophoblastic plate, in continuing
to thicken, develops lacunae into which the maternal capillaries empty and
promptly fill with plasma and red cells. These spaces greatly increase the
absorptive area and there is a corresponding increase in the amount of tropho-
blast. The very rapid growth of trophoblast that takes place in three days
is shown in the figure on page 6, where B to D represent the prelacunar
stage and E to H represent the second or lacunar stage. The third or villous
stage follows directly after the above stages. In the available material one
can plainly follow the formation of the chorionic villi and the differentiation
of cytotrophoblastic columns, the centers of which become transformed
into reticular connective tissue and capillary-forming cells and thus com-
pose the cores of the villi. The details of this transformation were previously
described by Dr. Hertig as referred to in a previous report (Year Book

CARNEGIE INSTITUTION OF WASHINGTON

Fig. 1. Drawings illustrating the enormous growth that occurs in the trophoblastic wall
(solid black) of the ovum in the four days following its parasitic attachment to the uterus.
Tissue materials are necessary for such growth and these are supplied by the luxuriant
uterine epithelium and the plasma and blood cells of the adjacent tissues. Previous to
attachment there is very little actual increase in the mass of the ovum. These eight stages
are all from monkey embryos shown at the same enlargement (X 75). Their ages are as
follows: A, 9 days; B, 9 days; C, 10 days; D, 10 days; E, 10% days; F, 11 days; G, 12 days;
H, 13 days.

DIVISION OF ANIMAL BIOLOGY 7

No. 33). The villous stage begins about the 15th day and progresses to
the completion of the placenta, the most important features of which can
be seen already on the 35th day.

Yolk-Sac and Gut Endoderm

Following the attachment of the ovum on the ninth and tenth days we can
speak of the third chapter in its development. With the auxiliary parts
of the ovum well on their way to differentiation there is an awakening of the
cells that are to form the embryo proper. This awakening is expressed by
their increase in number and by their orientation and arrangement into an
ectodermal disk or embryo disk. In this process the disk becomes set off,
both dorsally and ventrally, by fluid-containing spaces from the abutting
auxiliary tissues. The exact time relationships vary a little in different
specimens and still more so in different mammals, so that in the early stages
the appearance at the embryonic pole may be quite different, but apparently
the underlying principles remain the same.

During the past year the studies of the writer have been directed more
especially to the fluid space which develops ventral to the embryonic disk.
Whereas the dorsal space enlarges to become the amnion, the ventral space
enlarges to become the combined gut and yolk-sac cavity. The yolk-sac
is definitely something more than an embryonic vestige. Furthermore it
does not bud off from the inner cell mass in the form of a solid clump of cells,
thereafter acquiring a central cavity, as had been supposed. Nor is it at
any time an intrinsic part of, or homogeneous with, the gut tract. Instead
our specimens show us that the earliest cells of the yolk-sac are differentiated
from the primitive endoderm as a thin membrane between which and the
gut endoderm there arises the conjoint yolk-sac cavity and gut cavity.

This cavity ventral to the embryo disk is therefore dual in origin. It is
bordered on its dorsal part by cells that are to form the gut endoderm, an
induced product or migratory element from the disk itself; whereas the space
on its ventral part is bordered by the yolk-sac endoderm, which is a deriva-
tive of the primitive endoderm and is in fact an auxiliary tissue. The gut
and yolk-sac are thus different in origin and are always abruptly demarcated
from each other. The one becomes a definite part of the embryo and the
other is an auxiliary organ which in primates plays a temporary but ap-
parently very essential role in the metabolism of the embryo up to that
time when its functions are taken over by the placenta, a much more elab-
orate and efficient organ. Thereafter the yolk-sac regresses, although we
can usually find its degenerate remnants attached to the fetal membranes
at birth.

Young Human Embryos

Among the publications in the last number, volume 27, of the Contributions
are three accounts of presomite human embryos. This early period of
human development is imperfectly known because of the scarcity of well-
preserved normal specimens of that age, upon which our understanding
must be built. One of these specimens is that of Dr. J. I. Brewer studied in
the Anatomical Laboratory of the University of Chicago. This 15-day

8 CARNEGIE INSTITUTION OF WASHINGTON

specimen is certainly normal and is in a good state of preservation and is
destined to take its place as a standard 6f orientation in the procession of
stages through which the human embryo passes in its development.

A slightly younger specimen has been studied in this laboratory by Dr.
E. M. Ramsey. This specimen, known as the Yale Embryo, is estimated
to be between 13 and 14 days old. It was obtained at autopsy and a suf-
ficiently large block could be made to show fully the relations of the embryo
to the uterine wall. Neither this nor the Brewer specimen has the perfec-
tion in histological detail that we are able to secure in our macaque embryos,
and neither of them can be relied upon for some of the problems that involve
finer cytology and intercellular reactions. The student of human embryology,
however, is accustomed to such deficiencies and has been able to piece to-
gether his story from specimens, some of which are much less perfect than
these. It is to be remembered that at the end of the second week even the
gross general anatomy of the human embryo is still more or less obscure.

Among other things Dr. Ramsey analyzes the phenomenon of blood-sinus
formation around the newly implanted ovum. The Yale specimen illustrates
this particularly well and apparently it always occurs in normal specimens
as soon as decidua appears. The sinuses are found to consist of localized
dilatations of precapillary venules and their formation is an expression of
the marked response that occurs in the endometrial vessels under varying
hormonal and environmental conditions. Whether such localized alloca-
tions of blood plasma and red cells serve a nutritional function for the ovum
or whether the sinuses are a means of lowering blood pressure in the vessels
communicating with the lacunae, thereby shielding the embryo from pres-
sure extrusion, remains to be determined. Perhaps the most important part
of Dr. Ramsey's study is her analysis of trophoblast development, and her
conclusion that there is a normal correlation between it and the decidua and
the embryo proper. With the normal variation in these correlations estab-
lished one is then in a position to recognize the abnormal. It is also noted
that it is normal for the trophoblast to develop more luxuriantly on the
deeper hemisphere of the ovum where the food is more abundant than on
the side toward the uterine cavity. This is responsible for the apparent
invasion inward. Besides the correlated growth of the trophoblast relative
to other things, there is a regulation of its differentiation into syncytium on
the surface and into primitive mesoblast on the inner side, the more primitive
cytotrophoblast, later known as Langhans cells, being the germinal bed
for both of them. Normally a balance is maintained between these elements.
The occurrence of an imbalance between them in a specimen is evidence that
it is pathological. Dr. Ramsey illustrates this by a specimen from the
Carnegie Collection in which the supply of parent cytotrophoblast is ex-
hausted, being wholly converted into mesoblast on one side and syncytium
on the other.

The occurrence of "syncytial wandering cells" in the above specimen has
given Dr. Ramsey an opportunity to analyze their origin. There is some
evidence that these are not fetal cells but are transformed stroma cells, which
are in the process of being converted into pabulum for the advancing tropho-
blast. On that basis the multinuclear or giant cell character could be re-

DIVISION OF ANIMAL BIOLOGY 9

garded as an expression of degeneration. On the other hand, the distribu-
tion of the cells and the absence of other signs of degeneration leave the
matter in some doubt. Dr. Ramsey's study of this phenomenon serves to
call attention to a phase of implantation that has been largely overlooked.

A third human embryo, younger than either of the former, has been studied
by Dr. E. Scipiades, Jr., of Budapest, a guest of this laboratory as an ex-
change student of the Institution of International Education. This speci-
men carries special interest because of an associated clinical history of hor-
mone and "small dose" X-ray treatment for sterility. The embryo was
discovered in curettage material and fortunately the sections pass through
the ovum in a direction that discloses the implantation details. The tropho-
blast is primitive in character and as yet there are no villi. This places the
specimen in the group of very early ones.

ORGANOGENESIS

The studies of Dr. E. H. Norris on the parathyroid and lateral thyroid
glands will already be familiar to the readers of our embryological re-
ports. There is now to be added to these a reference to his study of the
human thymus gland, to which his investigations were extended. Part of
his work was done on the embryological collection in Dr. Jackson's labora-
tory and part on our own collection.

In his study of the morphogenesis of the thymus Dr. Norris comes to con-
clusions which diverge somewhat from those of Dr. Weller, who also had
worked in our laboratory and on the same material. This is wholesome and
tends eventually to bring us nearer to the correct solutions of these ques-
tions. A point emphasized is the cervical sinus, which Dr. Norris concludes
to be the primordium of the primitive thymic cortex and the source of Has-
sall's corpuscles, two very important assignments. Dr. Weller had concluded
that the cervical sinus is a product of the mechanical exigencies of the region
and is influenced by, rather than being the cause of, the development of
the thymus. It is clear that much study is still needed throughout the
region of the branchial pouches before we can unravel its many factors in
development. It may be that some help can be obtained through experi-
ment. The branchial clefts have been so heavily loaded with the philosophy
of recapitulation that it is difficult to separate out what is the real gill-cleft
phenomenon from what is the expression of other developmental factors of
the region. It is possible that recapitulation in our ways of thinking is
more inexorable than it is in the development of the embryo.

In his conclusions Dr. Norris derives the epithelial elements of the human
thymus from two distinct sources both of which are within the third branchial
complex. These two sources make it an ectodermal-endodermal structure.
The ectodermal source is the cervical sinus, which provides the primitive
thymic cortex and the HassaH's corpuscles, as noted above. The endodermal
thymus, arising from the third endodermal branchial pouch, gives origin to
the syncytial cytoreticulum of the gland. The thymic lymphocytes he
finds to be of mesenchymal origin, secondarily invading the gland. Other
elements of gland reticulum are derived from connective tissue cells in the
adventitia of vessels and from the gland capsule.

10 CARNEGIE INSTITUTION OF WASHINGTON

Embryologists have utilized the somites very largely as a topographical
scale against which the levels of the body are oriented. One difficulty has
been the determination of the first or most oral somite, with which they
must begin their count. There has been an uncertainty as to whether the
first somite of a later stage is the same as the first somite of the earlier
stages; that is, are new somites added in front or perhaps does the original
first somite disappear? Either of these events would alter the count. An
important study covering a survey of these occipital somites in a large num-
ber of human embryos has been made by Dr. L. B. Arey of Northwestern
University, and the results were reported in the last volume of the Contribu-
tions to Embryology. He finds that the first pair of somites usually undergo
regression both in size and in structure. By tracing this regression he con-
cludes that dedifferentiation plays a considerable part in the process. The
regression may be slow in some cases but usually in embryos of more than
20 somites the first remaining pair are actually second somites. Retarded
differentiation and beginning regression can be made out as early as embryos
of between 5 and 9 somites. For students of embryonic anatomy Dr. Arey's
careful work in this field will be of importance. Also it adds to the general
principles of development an instance of over-induction, eventually cor-
rected by the lack of supporting stimuli.

In studying the anatomy of the whale fetus Dr. R. Walmsley has covered
a field in which comparatively little systematic work had been done. Al-
though of peculiar interest because of its high degree of specialization, the
adult animal from its very size and its inaccessibility has rarely been avail-
able for study except in its skeletal form. In the fetus some of the difficulties
are obviated and the opportunity of studying four fetal specimens has been
well utilized by Dr. Walmsley not only to cover the fetal stages but through
them to interpret the conditions and problems of the adult. His oldest speci-
men was a mid-term fetus, and the other three fell within the first half of
pregnancy.

The respiratory mechanisms of the whale in adaptation to its habits of
submergence have been of great interest to the anatomist and they have re-
sulted in highly specialized structures that are foreign to other mammals.
The most striking peculiarities of the whale, however, are found in its
vascular system. Dr. Walmsley's investigations were largely concerned
with this system. He made a systematic study of the blood vessels through-
out the whole body, both as to their gross anatomy and as to their histology.
A striking generalized characteristic of the arteries was the breaking up of
what in other mammals would be a single trunk into a series of collateral
vessels, a condition adapted to a large volume of total blood together with
a low blood pressure. The feature of greatest interest was found to be the
retia mirabilia, especially the thoracic, which is associated with decrease in
lung volume during submergence, and the cerebrospinal retia, which serves
as buffer interposed between the arteries of the main parts of the body and
those intrinsic to the central nervous system. Dr. Walmsley concludes that
these peculiarities of the whale vascular system are not provisions against
a possible shortage of oxygen, for apparently such a shortage does not occur.
Instead, this highly specialized system is an adaptation to the differences

DIVISION OF ANIMAL BIOLOGY 11

of surface pressure under which their mode of life requires them to live.
It is thus understood why these specializations are more elaborate in the
adult than in the fetus and are largest in whales that can remain submerged
longest.

PHYSIOLOGY OF THE EMBRYO

Secretion in the Fetal Chorioid Plexus

Continuing his studies on the origin of function of the chorioid plexus in
the fetal brain, Dr. L. B. Flexner with the cooperation of Dr. R. D. Stiehler
has been able to show that the appearance of secretory activity of this plexus
is correlated with the development of a difference of potential between
stroma and epithelium and the initiation of an electric current between the
two tissues. It had previously been shown that cerebrospinal fluid changes
from an ultrafiltrate to a secretion at the end of the first third of pregnancy
in the pig. In the new studies attention is turned to the biochemical changes
that occur in the plexus at this transition period, when the plexus is changing
from a passive state to an active chemical machine.

For determining the potentials of epithelium and stroma use was made
of oxidation-reduction indicators and it was found that in the pre-secretory
period the epithelium and stroma of the plexus have the same potential. With
the onset of secretion, however, the potential of the epithelium rises some-
what and the potential of the stroma falls markedly until there is a potential
difference of 0.10 volt. This difference increases until in the last third of the
gestation period it amounts to 0.23 volt.

In the secretory plexus, in addition to the difference of potential between
epithelium and stroma it was also found that the basement membrane con-
ducts electrons. The electric current so established between epithelium and
stroma explains the selective transference of acid and basic dyes across the
basement membrane. In the pre-secretory plexus, since there is no difference
of potential between epithelium and stroma, there is no electric current and
consequently no selective transference of dyes.

In explanation of the changes in potentials of epithelium and stroma, it
is pointed out by Dr. Flexner that in the pre-secretory period indophenol
oxidase is in low concentration and equally distributed between epithelium
and stroma. As secretion begins this oxidase disappears from the stroma
and is found in much higher concentration in the epithelium. Indophenol
oxidase activates molecular oxygen for biological oxidations and in its pres-
ence, other factors being equal, the potential level of a tissue is raised. Thus
these changes in potential seem to hinge on the distribution of indophenol
oxidase.

In his studies of the biological processes underlying the formation of cere-
brospinal fluid by the chorioid plexus, Dr. Flexner has made an analysis of
the thermodynamics of ultrafiltration and has verified his theoretical deduc-
tions by experiments with sucrose solutions and to some extent with colloidal
solutions. In this way he has obtained criteria for distinguishing whether
the cerebrospinal fluid is a dialysate in equilibrium with the blood plasma,
or an ultrafiltrate of the blood plasma, or a true secretion involving energy

12 CARNEGIE INSTITUTION OF WASHINGTON

expenditure by living cells. In this work Dr. Flexner has found himself in
the enviable position of the biologist who on reaching one of his frontiers is
able to help himself out by making use of some of the pathways that have
been developed in a neighboring discipline.

CHROMOSOME STUDIES

Development of the Salivary Gland Chromosomes

Because of their unique interest an investigation has been made by Dr.
J. B. Buck of the embryology of the giant chromosomes which are found
in the larval salivary glands of Diptera. Using Sciara larvae he has traced the
steps of transformation of these chromosomes from their original state, when
in size and appearance they are like ordinary somatic chromosomes, until
they attain their enormous size and typical banded appearance. In doing
this he made measurements of the chromosomes, nuclei, cells, glands, and
larvae in the living state. The finer morphology of the chromosomes was
studied on fixed material for each stage of development.

It was found that the salivary gland attains its definitive number of cells
soon after it arises in the embryo within the egg. Its subsequent growth is
due entirely to increase in cell size and the greater part of this growth occurs
in the late larval stages. What is true of the cell is also true of the nucleus
and then in turn of the chromosomes, which compose 90 per cent of the
nuclear volume. The nuclear volume doubles every 1% days during the
period of the 4th to the 17th days, from which time to the beginning of
pupation it becomes progressively less.

As to the structure of the chromosomes, it is found that in the early em-
bryonic gland homologous chromosomes are paired, and are merely short
slender threads. From the outset, however, each thread exhibits enlarge-
ments which correspond to those of its homologue. Each of the threads soon
splits into two threads, retaining however some cross-connections. The
homologues are thus doubled and shortly before the larva hatches from the
egg these doubled homologues begin to twist or coil about each other and
fusion between homologous regions begins. There is thus produced a four-
stranded helically coiled flattened chromosome as early as 6% days after
the egg is laid. Each synapsed pair of doubled homologues soon appears
as a slender cylindrical and much elongated strand, showing diffuse cross-
bands at intervals which foreshadow the "banding" of the fully developed
salivary chromosome. During the succeeding larval stages the chromosomes
greatly increase in diameter, the banding becomes more pronounced, and
the coiling reaches its maximum. Before pupation the coiling relaxes and
the chromosomes become straighter, and this is the period of their greatest
growth. As pupation sets in, however, these giant chromosomes begin to
regress and finally during the pupal stage the larval salivary glands undergo
histolytic degeneration.

In reference to the development of the banding, Dr. Buck found that the
first ones to appear represent the heaviest bands of the definitive chromo-
some. They remain relatively unaltered during development, though they
tend to darken and some of them separate into doublets. The new, light

DIVISION OF ANIMAL BIOLOGY 13

bands, which become visible as development proceeds, appear in the length-
ening spaces between the heavier bands. They apparently do not split off
from the latter.

This investigation is being carried further but already it has uncovered
some very essential features which will need to be reckoned with by the
chromosome cytologists and by the searchers for the gene.

Chromosome Puffing and Chromosome Knots

In his studies on the giant salivary gland chromosomes in Sciara Dr. C. W.
Metz has turned his attention to the phenomenon of "puffing" and the struc-
ture of such regions. Instead of the characteristic banded structure the
chromosome may vary in certain particular regions by becoming greatly ex-
panded or "puffed." In such an area it is uniformly granular, resembling
cytoplasm as seen in fixed preparations. It is evident that the segment in-
volved has been increased in volume and that the increase is in the form
of small achromatic droplets. Intermediate degrees of "puffing" show bands
in various degrees of disintegration. Dr. Metz points out that the material
in these "puffed" regions is perhaps comparable to that of the "chromo-
center" in Drosophila, and if it is we must conclude that the "chromocenter"
is not inert. From the study of living cells in tissue culture we have learned
the wide range in form which cells may undergo with different physiological
states, and our recent observations on chromosomes and their chromatin
content tend to show that here, too, we have structures that are delicately
responsive to the state of the nucleus and the circumstances of the environ-
ment.

In a former report reference was made to the evidence obtained by Dr.
Metz of the presence of an insulating sheath surrounding the individual
chromosome. In a review of the occurrence of chromosomal knots he adds
further evidence of the existence of such a sheath. Simple knots are occa-
sionally found midway in the giant salivary gland chromosomes of Sciara.
It is evident that they arise early while the chromosomes are still small
threads, but since the knots always involve both homologues they must have
formed after the homologues had fused. The principal growth of the chromo-
some occurs after the completion of the knot, and this tends to make the
knot a snug one. A knot can form only in the presence of free movement of
the chromosome. At its initiation there must be a loop and the sliding of
one part over another. That fusion does not result during the process is ex-
plained by Dr. Metz by hypothesizing an insulating sheath. As the chromo-
some becomes thicker and the knot becomes tighter it would appear on
mechanical grounds that the segments involved would become deleted or,
if the tenseness sufficiently overcame the protection of the sheath, fusion
would follow and an inversion of segments would occur. Such events would
explain some of the well-known genetic experiences.

Multiplication and Reduction of Chromosome Groups

Last year an account was given of the studies of Dr. C. A. Berger on the
multiple chromosome complexes found in the larval ileum of the mosquito,
where repeated division of the chromosomes occurs without division of the

14 CARNEGIE INSTITUTION OF WASHINGTON

nucleus. That is, during the larval period the epithelial cells of the ileum
grow by increase in cell size to three or four times their original volume
without an increase in the number of cells. It is not until metamorphosis that
division of the cells occurs. As metamorphosis progresses these cells re-
peatedly divide with corresponding decrease in their size and in the number of
chromosomes until we come to the relatively small nuclei of the rebuilt im-
aginal ileum with its normal diploid number of 6 chromosomes. Here we have
compounding of chromosomes which may well be compared to that seen
in the giant salivary gland chromosomes. Since last year Dr. Berger's paper
has been completed in its final form and has been published in volume 27 of
the Contributions to Embryology.

GENETIC STUDIES

Genetic Units

In the last Year Book reference was made to the difficulties met in dis-
tinguishing between genie and non-genic material in the chromosome. Dr.
C. W. Metz has continued his consideration of this problem and at the end
of the additional year he still is unable to place his finger on the gene though
in the meantime he has made further additions to our knowledge of the finer
anatomy of the chromosome.

The problem has been approached from another aspect, namely, a study
has been made of small chromosomal deficiencies, which are either lost or
acquired as units and therefore might represent genes. Dr. Metz has thus
attempted to identify the smallest possible structure that, as a unit, may be
lost or acquired, and at the same time to determine the nature of this struc-
ture in terms of its visible chromatic and achromatic chromosomal constitu-
ents. For his material he has utilized Sciara ocellaris, which is particularly
favorable in that it is characterized by various small chromosomal deficien-
cies which may be found in ordinary stocks without radiation. These de-
ficiencies appear to be widely distributed in nature.

The general trend of evidence from the salivary gland chromosomes of
this form is that any of the transverse disks, including even the thin ones,
is divisible into two or more disks sufficiently independent so that one may be
lost without the other, or a similar one may be acquired. Dr. Metz has ana-
lyzed in detail eight examples of this kind of deficiency and has attempted
to determine: (1) what is the smallest unit that can be detected as a de-
ficiency? (2) what is the composition of this unit in terms of chromatic and
achromatic materials? and (3) what is thereby revealed as to the relation-
ship of the chromatic disks to the achromatic material? He found that these
questions could be answered at least in part. The smallest unit loss or
acquisition involves a single chromatic disk and the layer of achromatic
material on one side of it. As to the relationship of the chromatic disk to
the chromatic material matters remain uncertain. The evidence points
toward the chromatic rather than the achromatic materials as the genetically
important constituents. Both exhibit considerable variation in appearance,
but apparently the variation in the chromatic disks is largely due to varia-
tions in the amount and distribution of achromatic materials. Dr. Metz

DIVISION OF ANIMAL BIOLOGY 15

concludes that the heavy walled droplets, thought by some to represent unit
genes or chromomeres, are probably not unit structures and do not represent
unit loci.

Observations on Sciara Hybrids

For purpose of genetic and cytological studies several wild strains of
Sciara have been brought into the laboratory from various localities. Dr.
Metz has found among this material a new species of Sciara (S. reynoldsi)
which hybridizes with one of the more common laboratory species (S. ocel-
laris). The two species possess definite morphological distinctions. In
general appearance, however, the two species are so nearly identical that
their discreteness was not noted until it was found that many of the cross-
matings between them failed to give offspring and also that their salivary
gland chromosomes differ in pattern. Because of the importance of this
new species for genetic studies a taxonomic description of it has been pub-
lished by Dr. Metz for the information of other workers.

Preliminary hybridization studies of the above two species already have
been made by Dr. Metz and Mrs. E. G. Lawrence. Among the results ob-
tained by them are the following: (1) no offspring are secured from matings
of S. reynoldsi 9 X S* ocellaris $ ; (2) S. ocellaris 2 X S. reynoldsi S give
vigorous, viable offspring in large numbers; (3) apparently all hybrid females
are sterile; (4) hybrid males are not sterile; when mated with ocellaris
females offspring were obtained in eight out of ten matings; (5) many of
the hybrids are gynandromorphs, representing various types of mosaics of
male and female parts; (6) abnormal gonads are found very frequently; (7)
when yellow (a sex-linked mutant character) ocellaris females were mated to
wild-type reynoldsi males, the daughters were found to be "wild-type" and
the sons all "yellow"; (8) the males thus transmit only the chromosomes
received from their mothers and they thus behave genetically as if they
were pure S. ocellaris; (9) the original cross and backcross matings are suc-
cessful only when ocellaris is used as the female parent; (10) the hybrids
tend to be intermediate between the two parents in respect to taxonomic
characters; (11) the metaphase chromosome groups of the two species ap-
pear to be alike, each consisting of three similar pairs of rod-like chromo-
somes and one pair V-shaped; (12) in the salivary glands of hybrids the
chromosomes are associated in symmetrical pairs, but complete fusion is
found only in a few short regions. In their publication the interesting struc-
ture and incomplete fusion of the salivary gland chromosomes of these hybrids
are fully illustrated.

New Mutants in Sciara

Six new mutant characters in Sciara which have been found in this lab-
oratory among descendants of flies which had been exposed to radium, along
with two mutants which appear to be identical or reciprocal to two of them,
have been studied by Miss H. V. Crouse and Dr. H. Smith-Stocking. In
each instance the origin and description of the character and its genetic be-
havior have been completely analyzed by them. They have found that the
character "stop" is an autosomal dominant in S. coprophila, involving a
translocation between chromosomes II and IV. "Yellow" is a sex-linked

16 CARNEGIE INSTITUTION OF WASHINGTON

recessive in S. ocellaris. This character has already been referred to in
connection with the hybrids described above. Of the four mutations found
in S. reynoldsi, "puff" and "vesiculated" are autosomal dominants that are
lethal when homozygous. They may prove to be reciprocal or perhaps identi-
cal. "Jagged" is a sex-linked dominant that is lethal when homozygous.
"Ruffled" is a sex-linked dominant and closely linked to it is "Yellow," a
sex-linked recessive. The "yellow" mutations of S. reynoldsi and S. ocel-
laris appear to be reciprocal. These investigators conclude that the genetic
behavior of these mutant characters is proof of selective segregation in S.
ocellaris and S. reynoldsi.

CHEMISTRY OF BODY TISSUES

Improved Methods for Histochemical Analysis of Tissues

Dr. I. Gersh has adapted the Altman, freezing-drying technique for the
identification of the presence of chloride, phosphate-carbonate, and potas-
sium in muscle tissue. In this way he avoids diffusion of water-soluble
substances which had vitiated the studies of earlier workers. By embedding
the frozen-dried material in paraffin and sectioning at known thickness the
distribution of the substances can be studied and access of subsequent re-
agents is facilitated. The paraffin is removed by petroleum ether and this
allows silver reagents to penetrate the sections. Silver nitrate solutions
were used to precipitate chloride ions, alone or together with phosphate
and carbonate ions. The precipitated silver salts were reduced by exposure
to an arc light. Potassium was made visible by the use of sodium cobalti-
nitrite. The details of the procedure as worked out by Dr. Gersh will not
be given here. They have, however, been made available to other investi-
gators in the published account of his investigation.

As regards chloride, Dr. Gersh was not able to find any in the muscle
cells of the frog sartorius. It was present, however, in the interstitial and
collagenous connective tissue. When the muscle chloride concentration was
decreased or increased by suitable manipulation there was a corresponding
decrease or increase in the amount of chloride visible in the connective
tissue spaces. In all cases there was more visible chloride present in col-
lagenous connective tissue than in reticular connective tissue.

In all the muscles examined phosphate-carbonate was seen in the muscle
cell, as well as in the connective tissue surrounding it. It was determined
by the difference between the color intensities produced by two reagents, one
an acidified silver nitrate nearly saturated with silver chloride and the other
a silver nitrate nearly saturated with silver chloride and silver phosphate. It
was found that the distribution of phosphate-carbonate is uniform through-
out the cytoplasm and does not have a linear arrangement as described by
earlier histochemists.

Potassium was determined with sodium cobalti-nitrite at a low tempera-
ture. The crystals representing potassium are seen uniformly throughout the
whole cell cytoplasm. There is some variation in the density with which the
cell is packed but it is slight. Perhaps the variations are not easily seen
because the crystals are so numerous. Like phosphate-carbonate, potassium

DIVISION OF ANIMAL BIOLOGY 17

is distributed uniformly in the muscle fiber, without relation to longitudinal
or transverse striations. Dr. Gersh in these observations has been able to
demonstrate the intracellular distribution of these four ions in striated muscle
fibers, concerning which we have heretofore depended on deductions and
assumptions. He confirms by direct histochemical methods the fact that
potassium is present in very large amounts in the cytoplasm, that phosphate-
carbonate is present in moderate amounts, and that chloride is completely
absent.

Distribution of Chloride in Gastric Mucosa

The methods which we have seen developed in the preceding paragraphs
provide a technique which is sensitive, specific, and devoid of diffusion errors.
With it Dr. Gersh has attempted to clarify the problem of the site and mode
of formation of hydrochloric acid in the stomach. The gastric mucosa of
dogs was studied during the resting phase and during the height of activity.
He found that during rest chloride is absent from the cytoplasm of all gland
cells. Traces of it are, however, present in the secretion granules of the
zymogenic gland cells. Chloride is found in the lumen of the gland and in
still larger amounts in the gastric pits into which the gland lumina empty.
Furthermore, it is found evenly distributed throughout the connective tissue
spaces of the mucosa and submucosa.

In the actively secreting mucosa the distribution of chloride was found to
be essentially the same as in the resting stage. It was found in the same
places but was present in greater amounts. More chloride is visible in the
cytoplasmic inclusions of the zymogenic cells and the spaces of the connective
tissue. The cytoplasm of all the glandular cells is free of chloride, just as
was seen in muscle fibers.

Dr. Gersh finds himself unable to explain the presence of chloride in the
secretion granules of the zymogenic cells. Its presence in the connective
tissue spaces is naturally correlated with greater amounts of chloride-con-
taining tissue fluid and lymph, formed during glandular activity. It is sug-
gested that the protein chloride is extruded from the parietal cells as rapidly
as it is formed and none of the compound is stored in the cytoplasm. It may
still be true that the parietal cell is the one whose specific activity results in
the secretion of hydrochloric acid, even though our present methods fail to
detect it in its early secretory phases.

Histochemistry of the Fate of Colloidal Calcium Phosphate

A series of experiments have been conducted by Dr. I. Gersh dealing with
the metabolism of calcium and phosphorus in the blood. Following in-
travenous injections of rats and dogs, in some cases with calcium and phos-
phate salts, and in other cases with colloidal calcium phosphate suspended
in horse serum, he was able to follow the mechanism existing for the rapid
removal of excess colloidal calcium phosphate from the blood, namely, by
the phagocytosis of the particles by the macrophages of the liver and spleen
and to a less extent of the bone marrow. The phagocytosed particles are
retained by the macrophages a relatively short time and are then liberated.
The whole mechanism is a transitory one. His experiments show that the

18 CARNEGIE INSTITUTION OF WASHINGTON

degree of phagocytosis is influenced by variations in the amount of colloidal
compound present in the blood stream. The macrophages of the lymph nodes
take no part in this, as long as the colloidal particles are confined to the blood
stream. If, however, colloidal calcium phosphate is injected subcutaneously
or into the muscles so that it enters the lymph and tissue fluid, phagocytosis
in lymph nodes may then take place.

As has been said, the colloidal particles of calcium phosphate are retained
in the cytoplasm of the macrophages but a short time and are then liberated.
This subsequent liberation of the calcium and phosphate into the blood ap-
pears to be responsible for the delayed rise in serum calcium which is experi-
enced particularly after the intravenous administration of phosphate. It
is proposed by Dr. Gersh that the granules of calcium phosphate in the cells
may be turned into the constituent calcium and phosphate ions, which leave
the cells as fast as they are formed. While this process continues the calcium
and phosphate in concentrations in the blood plasma are reduced by their
passage through the capillaries into the urine, feces, and tissue fluid.

The histochemical method used by Dr. Gersh for testing the content of
phosphate in the sections revealed it as a precipitate of black or brown gran-
ules in the phagocytic cells. For testing the presence of calcium in the
sections, after the freezing-drying-embedding technique and the removal of
the petroleum ether, they are treated with a water solution of sodium alizarine
sulfonate, which is drained off and replaced by chemically pure glycerine.
Calcium in such sections appears as an orange color and the granules are
less numerous and not as discretely separated as after the application of
the silver reagent. With this much accomplished it is not too much to hope
that a test may be found that will reveal these substances differentially in
living cells.

TISSUE CULTURE

Lymphocytes and Monocytes

Using lymph node explants, Dr. W. H. Lewis has studied the emigration
from them of lymphocytes and small monocytes. As they first make their
appearance, they are about the same size and could be mistaken for each
other. Dr. Lewis finds, however, that they are two different types of cells
and that the lymphocyte does not become transformed into the monocyte.
The two types can be distinguished by their mode of locomotion as well as
by their morphological details. The lymphocytes may divide but they rarely
live more than a few days. The monocytes, in contrast, increase in size,
multiply, and survive for many days.

Cultivation of Cancer Cells

A review has been published by Dr. W. H. Lewis of his studies on the
cultivation and cytology of cancer cells. This investigation has extended
over a period of several years and includes observations on 17 rat sarcomas
and 160 dibenzanthracene mouse sarcomas. He confirms his previously ex-
pressed opinion that cancer cells are permanently altered cells. They are
new types, derived from normal and usually healthy ones, which have been
permanently altered by environmental influences or various sorts of agents.

DIVISION OF ANIMAL BIOLOGY 19

After the normal cells have undergone the initial alteration into malignant
cells the special environmental influences or agents which produced them are
no longer necessary for the maintenance of their peculiarities.

Dr. Lewis finds that in tissue cultures the maligant cells are visibly dif-
ferent from normal ones and from each other. They retain their peculiar
characteristics from one generation to another when serially transplanted
from animal to animal and for months or even years. From six of the tumors
malignant cells were cultivated "in glass" for two to over four years. In
that way pure colonies of the malignant cells were obtained which retained
both their cultural characteristics and their malignancy. When inoculated
into animals typical tumors resulted. From these in turn pure colonies of
characteristic malignant cells were secured and these also produced typical
tumors.

In the dibenzanthracene mouse sarcomas there were not as many varieties
of malignant cells as in the rat tumors, nor were they as different from one
another as were those of the rat sarcomas. The malignant cells from them
were, however, visibly different from normal ones, and they could be followed
in subsequent generations by comparison of photographs of the primary
tumors with those of descendent cultures.

In roller tube cultures where cells have been carried on for three or four
months, there were found many large multinucleated giant cells of skeletal
muscle origin in addition to the fibroblast type of malignant cells. Further
study has revealed that these giant cells are muscle cells altered by the
invasion of the muscle by malignant cells but are not themselves malignant.

Transplantability of Induced and Spontaneous Tumors

A study of the transplantability of sarcoma tumors induced by dibenzan-
thracene and of spontaneous mammary gland carcinomata in four pure in-
bred strains of mice has been made by Mrs. M. R. Lewis and Mrs. E. G.
Lichtenstein. They found that every one of the 200 tumors they induced
in their four inbred strains proved to be transplantable into all the mice of
the strain in which the tumor arose. Out of 123 tumors which were trans-
planted to alien strains only 9 grew, that is, 114 proved to be strain specific.
This resistance of mice of one strain to tumors transplanted from another
strain was referred to in a previous report (Year Book No. 35). It was also
reported at that time that this resistance could be broken down. Since
then more has been learned as to the range within which this can occur.
Fourteen of the tumors that were strain specific when implanted in normal
young mice of alien strains lost their strain specificity when they grew in
a repeatedly implanted host of an alien strain, so that they were thereafter
transplantable not only into mice of their original strain and of the treated
strain, but also into mice of other strains.

In the study of 80 spontaneous mammary gland tumors it was found that
they not only were strain specific but also largely retained this specificity
even though repeated inoculations were made into hosts of alien strains.
There were a few exceptions in which the tumors became transplantable into
mice of a closely related strain. Where mice already had a spontaneous
mammary gland tumor, they were not immune to the development of addi-

20 CARNEGIE INSTITUTION OF WASHINGTON

tional spontaneous mammary tumors. Some of the mice developed as many
as five mammary gland tumors during the course of two months. These
same animals, however, were somewhat refractory to the growth of similar
tumors grafted from other mice even though of the same strain. The in-
dividuality of tumor growth was well shown in a series of experiments in
which a carcinoma was implanted on one side of a mouse and a sarcoma
on the other. Both tumors grew in such cases and were transplanted through
many generations in this manner. They each retained their own charac-
teristics, and microscopic examination showed one to be an adenocarcinoma
and the other a large spindle cell sarcoma.

A Useful Culture Tissue

It has been found by Dr. W. Mendelsohn that explants from the testicle
of the adult rabbit can be successfully grown in roller tube cultures. From
them he obtains extensive growths of epithelium suitable for testing the
viability of epithelial cells in the present of arsenical drugs, hormones, toxins,
and viruses. These growths also are suitable as a culture medium for the
growth of Spirochceta pallida.

Fragments of the testicle are distributed inside the tubes and held in place
by heparinized chicken plasma. As a nutrient medium rabbit serum is used
with a balanced salt solution. Locke solution can be substituted for the
balanced salt solution. After seven days areas of liquefaction occur near
the explants but these can be repaired by clots of chicken plasm and fresh
nutrient fluid substituted for the old. In this way the cultures can be main-
tained three weeks or longer if desired. There appears to be no difficulty
in making permanent mounts of such growths.

The first outgrowths from the explants are chiefly fibroblasts and endothe-
lial cells. Later broad sheets of germinal epithelium extend from the con-
voluted tubules. Occasionally Sertoli cells are seen. Apparently sperma-
tozoa may undergo maturation from the spermatocytes in this roller tube
culture.

STUDIES OF THE PITUITARY GLAND

Tissue Cultures of the Hypophysis

The study of the pituitary gland in tissue culture has been followed for
several years by Mrs. M. R. Lewis. She found that such cultures taken
from all the ordinary laboratory animals grow rapidly and abundantly, re-
gardless of the age of the animal from which the gland is obtained. They
grow particularly well in tube cultures. The cells retain their differentiation
and continue to form their specific granules, though the granules are fewer
than in the original tissue.

It was found that cells grown in cultures for as long as fifty days con-
tinued to produce blood-pressure-raising and melanophore-expanding hor-
mones. In an effort to correlate cell types with specific hormones animals
were sought in which cell types were so segregated that particular regions
could be dissected out for transplantation. In the mouse the pars inter-
media is free of pars nervosa tissue. In the chicken and armadillo the pars
nervosa is free of other lobe tissue, whereas in the dogfish and skate the

DIVISION OF ANIMAL BIOLOGY 21

pituitary cells are segregated into six separate lobes. The melanophore hor-
mone was located in two of these latter lobes and continued to form in cul-
tures. Apparently tissue culture affords a valuable tool for determining
specific functions of the pituitary cell groups, at least in the case of the
hormones belonging to the posterior lobe. The hormones of the anterior
lobe are more complicated in their activity and this has made them more
difficult to identify. A review of the present status of her studies was given
by Mrs. Lewis before the Association for Research in Nervous and Mental
Disease.

Cytology of the Hypophysis

In a previous Year Book an account was given of the studies of Dr. I.
Gersh on the relation of the histological structure of the posterior lobe of the
hypophysis and the pressor, oxytocic, and antidiuretic hormones which are
generally assumed to originate there. He was able to show that the hyaline
bodies of Herring, which had been thought to be a secretion antecedent, are
an artifact and are not present when the tissue is prepared under the best
conditions. This left only neuroglia cells as the local source ; unless one con-
cluded that these three hormones were made elsewhere and transported by
the blood stream and deposited through means of a special capillary perme-
ability and stored in the posterior lobe.

During the past year further study of the parenchymatous cells of the
posterior lobe in rats has led Dr. Gersh to the conclusion that some of these
cells are really glandular and that they produce and secrete the antidiuretic
hormone. This posterior lobe glandular cell has been found by him in a wide
variety of mammals and in pigeons and in chickens. It is characterized by
the presence of either granules or lipoid droplets which can be seen in fresh
mounts and which fill the cytoplasm and extend out into the cell processes.
In the rat these droplets are rich in neutral unsaturated fats ; in some animals
there are no visible lipoids. A characteristic feature of this glandular cell is
that it appears early in embryonic life and that the number and size of the
cells and of their inclusion bodies increase throughout life, reaching their
greatest prominence in rats two and a half years old. Owing to the fact that
there is a normal range in the number and size of these posterior lobe glandular
cells in any particular gland, Dr. Gersh was able to show that fluctuations
occur within this range which are correlated with the dietary intake of water.
This fluctuation could be controlled experimentally. After rats have been
restricted to a relatively dry diet for a week the glandular cells are present
in greater number and are larger. On the other hand when the experimentally
dehydrated rats are given free access to water, the number and size of the
differentiated cells promptly revert to the normal range prevailing in un-
treated rats. Thus Dr. Gersh establishes a significant correlation of cellular
activity and morphology with the hypersecretion of antidiuretic substances,
and perhaps also of oxytocic substances.

It may be added that among the parenchymatous cells of the posterior lobe
there are many that are relatively undifferentiated, but which during the
hyperplasia, which follows the stimulus to hypersecretion, become trans-
formed into the fully differentiated form. The differentiated and the rela-
tively undifferentiated varieties vary inversely in number.

22 CARNEGIE INSTITUTION OF WASHINGTON

Nerve Terminations in the Posterior Lobe

Using pyridine silver preparations and fresh pituitaries of young rats per-
fused with methylene blue, Dr. C. McC. Brooks and Dr. I. Gersh have suc-
ceeded in demonstrating nerve fibers which pass down on the hypophyseal
stalk to terminate in pericellular baskets around the glandular cells of the
posterior lobe described in the preceding paragraphs. The endings almost
completely enclosed the cells in a close-meshed network. The fibers belong
to the hypothalmic hypophyseal tract. It was found that they are unaffected
by the removal of the superior cervical ganglion, which would remove them
from the category of the sympathetic chain, if that were necessary.

The demonstration of this nerve supply to the posterior lobe glandular
cells gives us an explanation of the phenomena of pseudo-pregnancy, which
had been recognized as requiring the transmission of nerve stimuli. It also
becomes clear that section of the pituitary stalk would lead to degeneration
of these terminations and an accompanying severe diabetes insipidus.

REPRODUCTIVE SYSTEM AND ENDOCRINOLOGY

The Gilfillen-Gregg Skin Test for Pregnancy

A theory has been advanced that the abundant supply of prolan in the
blood of pregnant women should render these individuals immune to further
injections of urinary prolan, whereas the non-pregnant woman should be
prolan-sensitive. Were this true it would constitute a simple and economical
test for pregnancy. Two guest investigators in the laboratory, Dr. S. Saglik
and Dr. E. Scipiades, Jr., have tested this technique on animals. After fail-
ing to obtain differential reactions in rats, guinea pigs, and rabbits, they made
experimental injections of prolan in a series of monkeys, in a few of them in
the form of antuitrin-S and in others in the form of follutein. Here, too,
the results proved negative.

For purposes of control and as a test of the potency of the hormone used
on the animals, skin tests were made with follutein in pregnant and non-
pregnant women. Of 19 non-pregnant women only 11 gave the postulated
reaction, whereas of 23 pregnant women, whose pregnancies varied between
16 and 40 weeks, 6 reacted in a manner expected only in non-pregnant women.
It is thus clear that this test is not sufficiently reliable to replace the standard
Aschheim-Zondek or Friedman test.

Time of Ovulation

In reporting observations on the formation of uterine epithelial plaques
in the process of implantation of young monkey embryos, Dr. C. G. Hartman
assembled and reported his records on ovulation. Among 300 ovulations
accurately diagnosed, all occurred between days 8 and 16 with the exception
of 5, which fell irregularly outside that period. This seems to be a mechanism
whose precision is rarely surpassed among biological phenomena.

Alleged Birth of Triplets in the Macaque

Though multiple births may occur in the rhesus monkey it has been shown
by Dr. C. G. Hartman that one must be on guard against being misled

DIVISION OF ANIMAL BIOLOGY 23

by a tendency to kidnaping that prevails among certain aggressive mother
monkeys. In a case of apparent triplets it was possible for Dr. Hartman to
show that two other recent mothers in the same cage had been deprived of
their young, and also he obtained the conclusive evidence provided by the
fact that the appropriative mother had but one recent corpus luteum.

The Anthropoid Ovary

The opportunity of studying the ovaries of three gorillas, two chimpanzees,
one orang-utan, and one gibbon has been well utilized by Dr. S. Saglik, a
guest of this laboratory from the Gynecological Clinic, Gulhane Hospital,
Istanbul, in giving us an analytic description of the anthropoid ovary. He
has also compared these ovaries with those of man and with those of the Old
and New World monkeys.

Dr. Saglik finds that primate ovaries can be arranged in a series on the
basis of their general similarity to the human ovary and he arranges them
as follows: orang-utan, chimpanzee, gorilla, macaque, cebus, gibbon, Allouata,
and Ateles. Here then we have another organ which would call for a very
different phylogenetic tree from that demanded by the skeleton.

Menstruation

A study of the incidence of menstrual cycles without associated ovulation
has been made by Dr. C. G. Hartman on 300 female monkeys of the Carnegie
colony, concerning all of which he possessed fairly complete biological rec-
ords. These animals with few exceptions were purchased from animal dealers
and about one-third of them were superior specimens. Such animals ovulate
either at once after arrival or at least after a few months' period of acclimati-
zation. Another third of the animals received were inferior ones that either
did not menstruate at all or menstruated without ovulation. The remaining
third of the animals were intermediate in quality. They remained in excellent
health but ovulated less reliably or in some instances never. This material
provided Dr. Hartman with the opportunity of studying a very large number
of cycles, a sufficient number to determine their principal variations. Of
particular importance were his determinations of the frequency of non-
ovulatory cycles.

On analyzing the non-ovulating monkeys he found that the cycles could
be separated into two groups, those in which the non-ovulatory cycles may
be regarded as normal, and those in which the occurrence is pathological.
His records include 1000 cycles in which non-ovulatory cycles occurred
during the non-breeding season, from May to September. This appears to
represent normal behavior. Also non-ovulatory cycles are normal in ado-
lescence, of which there were 240 records. Likewise in the pre-climacterium
and during recovery from pregnancy and lactation non-ovulatory cycles are
normal. On the other hand, in 260 animals there were 1075 cycles in which
there was no ovulation and which must be classed as abnormal or patholog-
ical. Some of these animals were palpably sick, and either did not menstruate
at all or menstruated without ovulating a few times before death. About
30 per cent of the animals fell in this group. Then there are some apparently
healthy animals which never ovulate or else only occasionally ovulate. Of

24 CARNEGIE INSTITUTION OF WASHINGTON

the observed non-ovulatory cycles 17 per cent belong in each of these two
groups. Some animals are unpredictable and ovulate about one-half the
cycles of the breeding season. Such animals yielded a number of our finest
embryos. Recently acquired animals are very likely to skip their ovulations
for a time after their arrival. Some were with us two years before their
ovulations started, some one year, and others began ovulating during the
first year. Then among even the best animals there were some who occa-
sionally failed to ovulate at the normal times. About 10 per cent of the non-
ovulatory cycles fell in this group. From these records it is seen that the
non-ovulatory cycle is a very definite thing and becomes a factor that must
be reckoned with in consideration of the occurrence of sterility.

Further studies have been made by Dr. Hartman on the hormonal control
of menstruation. He has found that by periods of daily administration of
testosterone in a monkey which has previously been regular in its menstrual
cycles the cycle can be lengthened to 38 days as against 25 to 28 days previous
to the experiment. In animals which have been castrated the bleeding which
usually follows within a few days was inhibited by daily administration of
testosterone. Also the menstrual bleeding which in favorable animals uni-
formly occurs following the injection of amniotin can be inhibited over pro-
longed periods. Thus Dr. Hartman shows that testosterone has an action
upon menstrual control closely simulating that of progestin, just as it also
simulates progestin in stimulating mammary development and in inhibiting
the vaginal mucosa.

At this point reference should be made to the light thrown on the menstrua-
tion problem by the studies of Dr. J. E. Markee done in cooperation with
Dr. Hartman. They made transplants of endometrium according to Dr.
Markee's method and were able to follow the vascular changes by direct
observation. This work is now in course of final preparation for publication.
It will be reviewed in full in my next report.

Hormone Injections in Young Alligators

Before his appointment on the Johns Hopkins staff, Dr. T. R. Forbes
had already, under Dr. R. K. Burns, Jr., made his experiments on the induc-
tion of a precocious development of the reproductive tract in the immature
alligator by the administration of hypophyseal extracts. He had also studied
the effects of female sex hormone injections (cestrone) in young alligators
and found that it produced a marked hypertrophy of both ovarian and
testicular cortex, along with greatly hypertrophied oviducts in the females
and some development of the male vestigial mullerian ducts. This work has
been published during the past year. Dr. Forbes has continued his hormone
studies on the sexually immature alligator. He has investigated the effects
of prolonged injections of testosterone in recently hatched animals and found
them responsive to this hormone. In 14 females moderate hypertrophy of
the oviducts took place, although the change in the ovaries was less definite.
In the male the testes were twice as large as those of the control animals and
there was definite hypertrophy of the vestigial mullerian ducts and of the
penis. The wolffian ducts and the wolffian bodies were found unresponsive
in both sexes to injections of these sex hormones. If we accept them as

DIVISION OF ANIMAL BIOLOGY 25

embryonic organs that perform an essential but temporary service for the
embryo it removes them from the group of reproductive organs and would
explain their failure to respond to either testosterone or cestrone.

Tissue Culture of Endocrine Organs for Purposes of Transplantation

Some tentative experiments have been made by Dr. G. 0. Gey toward ob-
taining pure strains of thyroid and parathyroid cells in continuous tissue
culture from which homologous grafts can be made on individuals who
through deficiencies of their own need these specific endocrine secretions.
Thus far a number of successful grafts of thyroid cultures have been made in
dogs and also a few parathyroid grafts. The advantage of tissue culture
grafts is that in this way the desired endocrine cells can be acclimated to a
tissue culture medium that is composed largely of the recipients' plasma and
serum, thereby increasing the probability of their survival and functional
activity.

Experiments on Castrated Animals

In recently castrated young male rats it has been found by Dr. J. Ball
that the female hormone estrin, if given in daily injections of proper amounts
(50 to 100 rat units), will definitely increase or completely restore their sex
activity. The experiments were conducted on six male rats which were
castrated at about four months old and the tests were begun two weeks
later. Quantitative records were made both of their mating behavior and
of their motor activity as registered by the revolving drum. The amount of
hormone used was regulated by the response of the individual animal. After
the castrate level of sex activity had been determined a sufficient amount
of the hormone was given in daily injections to bring out an unquestionable
response in each rat. From the results of these experiments Dr. Ball reached
a conclusion that will be of interest to students of behavior, namely, that
the function of this estrogenic hormone in the adult animal is not so much
to organize the mating behavior pattern as it is to activate a pattern already
laid down through other influences.

New observations have been made by Dr. C. G. Hartman on the results
of castration in pregnant monkeys. Two animals castrated at the end of
the third month of gestation carried their fetuses to full term. Three others
castrated on the 46th, 35th, and 31st day, respectively, were progressing
normally two months later. These results harmonize with the fact observed
by Drs. Hartman, Corner, and Bartelmez that the corpus luteum of the
rhesus monkey is active only during the first four weeks of pregnancy, at
which time it markedly regresses. Theoretically its removal at any time
thereafter should not interfere with the continuance of pregnancy and, as
seen in these experiments, it does not.

CENTRAL NERVOUS SYSTEM
Cerebrospinal Fluid

In his lectures given at the University College, London, Dr. L. H. Weed
pointed out the importance to many fields of anatomical investigation of
intimately combining anatomical and physiological thought, and paying

26 CARNEGIE INSTITUTION OF WASHINGTON

equal regard to structure and to function. It was not necessary for Dr.
Weed to point this out, since his own example in the study of the coverings
of the brain and the specialized fluid that is contained within them had long
since provided us with a brilliant demonstration of the advantage of blend-
ing these two disciplines.

The researches of Dr. Weed upon the cerebrospinal fluid now reach back
25 years. During that time he, along with a group of able coworkers, has
unraveled an important series of fundamental problems regarding this in-
tricate system, concerning which little was known when his investigations
were starting. Under his guidance we have seen, as the readers of the
Carnegie Year Books will know, the histology and embryology of the
meninges clarified. This was followed by the demonstration of the sources
of the cerebrospinal fluid and the pathways of its return to the venous sys-
tem. There then followed the series of experiments which showed that the
absorption of cerebrospinal fluid is the product of two factors, a hydrostatic
one being the difference between the subarachnoid pressure and intracranial
venous pressure, and the other the colloid osmotic pressure of the blood.
This promptly led to the revelations regarding the pressure relationships be-
tween the cerebrospinal fluid and that in the cerebral veins, under the prin-
ciple of the bony wall of the cranial cavity and the vertebral canal serving
as a rigid container. There was then found the provision of elasticity which
permits a dislocation of fluid on change in position by means of compensating
dilatation and contraction of the intradural vascular bed, the cerebral venous
pressure at the same time remaining constant. Associated with the latter
experiments, a better hypothesis could be arrived at as to the primary func-
tion of the cerebrospinal fluid. It is owing to these researches of Dr. Weed
that we now see it as a means of providing a prompt reciprocal volume and
pressure adjustment when changes occur in the volume of the vascular bed
or in the nervous tissue.

Effect of Inactivity on Nutrition and Growth of Muscle and Bone

The investigations of Dr. S. S. Tower on the isolation of the lumbar en-
largement of the spinal cord in young growing animals has been extended
to its trophic effect on the muscles and bones normally innervated from that
source. In her experiments the cord was transected above and below the
lumbo-sacral enlargement and all its posterior roots cut. When this is
done the dependent muscles lose all ordinary activities including muscle
tone. It was found that for purposes of these experiments young animals
may survive several months and provide us with a method of studying the
regressive changes which follow nerve section. Also in such experiments one
can discriminate between effects of inactivation and those of nerve degen-
eration.

The three puppies used by Dr. Tower were studied 2, 5, and 6 months
respectively. By the nature of her experiment all ingoing nerve impulses
were excluded from the isolated cord, which nevertheless survived along
with its dorsal root ganglia and peripheral nerves, without developing within
itself any nervous activity. Since Dr. Tower had previously shown that
severing of the posterior roots is without appreciable trophic influence on

DIVISION OF ANIMAL BIOLOGY 27

skeletal muscle, any trophic disturbances resulting from these experiments
would therefore have to be ascribed to the inactivation.

It was found that atrophy and metaplasia of muscle tissue into fibrous
tissue, atrophy and destruction of subsarcolemmal nuclei, and interstitial
fibrosis are all characteristic of inactivation of skeletal muscle. Macroscopi-
cally such muscles can be seen to be atrophied and they develop contrac-
tures. Microscopically the fibers are smaller in all dimensions, pale stain-
ing, and in the process of transformation into fibrous tissue, and the inter-
stitial fibrous tissue is increased. The innervation remains largely intact.

All these things occur also in denervated muscle. But when a muscle is
denervated it shows a rapid proliferation and change in character of the sub-
sarcolemmal nuclei, which changes do not follow inactivation alone. This
specific nuclear proliferation must be attributed to the degeneration of
nervous tissue. Dr. Tower thus finds that the trophic control of muscle by
the nervous system requires both physical integrity of innervation and
nervous activation.

In analyzing the effects of inactivation on the postnatal growth of bone
it was found that the long bones of the leg were normal in length and in
their general configuration, features which appear to be intrinsic. In thick-
ness and certain details, such as elevations at muscle attachments, they were
underdeveloped. These then depend on extrinsic factors which in the above
experiments were abnormal because of the presence of muscle inactivity.
Special trophic nerves continue to be unnecessary to Dr. Tower for the dis-
cussion of the nature of trophic control of tissues.

Electrophysiology of Nerves

It is only recently that any of our group have participated in investiga-
tions on the electrical properties of functioning nerve fibers. During the
past year Dr. H. A. Howe in cooperation with Dr. D. A. Clark has made
observations on fiber action potentials in the fiber tracts located entirely
within the central nervous system. Observations on fiber action potentials
had previously been restricted to peripheral nerves.

Dr. Howe and Dr. Clark studied the changes produced in the electrical
potentials of the tracts within the cervical spinal cord following induction
coil stimulation of the pyramidal tracts which lie on the ventral surface
of the medulla oblongata, in the cat. They were able to demonstrate poten-
tials somewhat analogous to those characteristic of peripheral nerves. The
responses, however, were very complex and evidently included the activity
of many fiber pathways. Owing to the structure of the cord it was not pos-
sible to determine the correlation between conduction velocity and threshold
as has been done with peripheral nerves. Under the conditions of their
experiments they obtained potentials which in form, rate of conduction,
and resistance to asphyxia gave the picture of neuronic fiber activity with-
out synaptic intervention.

These investigators applied their stimuli to the pyramidal tracts by means
of a bipolar electrode having two silver contacts set flush in the end of a
bakelite rod. This rod was inserted tightly into a trephine hole through
the base of the skull, in a manner that avoided blood loss or leakage of

28 CARNEGIE INSTITUTION OF WASHINGTON

cerebrospinal fluid. The resultant disturbances were registered by coaxial
needle electrodes inserted into the cord at different distances from the point
of stimulation. The two levels chosen were an upper one at the level of
the second cervical vertebra and a lower one at the level of the fifth cervical
vertebra.

Dr. S. S. Tower participated in a study of impulses as they pass through
a sympathetic ganglion and into the nerves beyond it. She had the privilege
of working with Dr. D. W. Bronk and his associates, who are experienced
investigators in the field of electrophysiology of nerves. Their experiments
consisted in stimulating the preganglionic fibers, rami to the stellate gan-
glion from the spinal cord, and recording the action potentials in the rela-
tively long inferior cardiac nerve, to which the impulses were transmitted
through the ganglion.

It was found that the conduction velocities in the nerve studied had a
considerable range (1.4 to 0.6 meters per second), and there is a consider-
able temporal diversity in the maximum potential. Following the peak
there is a positive after-potential which may be increased during the course
of a tetanus. Likewise a negative after-potential develops after a tetanus.
A rested nerve does not generally show a negative after-potential.

The significance of the action potential records which are yielded by the
oscillograph is not altogether clear, and it is necessary at present to study
them in all their details and under all possible experimental conditions.
Among other things it was found by these investigators that a rapid series
of preganglionic impulses initiates a single but dispersed series of postgan-
glionic impulses. The records show that the individual nerve cell discharges
but one impulse for each series. The dispersion appears to be due to dif-
ferences in conduction time for the various fiber pathways through the
ganglion. It was also found that the number of ganglion cells that respond
to a preganglionic stimulus may be modified by various things. Arrest in
the blood circulation decreases the number, whereas repeated stimuli can
build up a larger response even in a non-circulated ganglion. Perfusion of a
ganglion with drugs also modifies the nature of the responses. Although
some of the terminology, the technique, and the character of the records
are somewhat confusing to one who is not oriented in such matters, it is
to be remembered that the workers in this field are collecting observations
that lead to something more tangible as to the nature of the conduction of
nerve impulses than the pure speculations which formerly were our sole
resort. Some of the ground work in the electrophysiology of protoplasm was
done with Valonia, that interesting primitive organism which abounds in
the waters at the Tortugas Laboratory.

Regeneration of the Facial Nerve and Associated Tics

In Year Book No. 35 a brief account was given of branched axones of
the facial nerve in monkeys following experimental injury of that nerve.
The results of those experiments have been published during the past year
in final form in the Archives of Neurology and Psychiatry under the author-
ship of Dr. Howe, Dr. Tower, and the late Dr. A. B. Duel, who were
aided by a grant from the Carnegie Corporation. These investigators have

DIVISION OF ANIMAL BIOLOGY 29

established, both physiologically and anatomically, the fact that in regenera-
tion of the facial nerve, following injury, its axones at that site undergo
branching and subsequently innervate widely separate muscles and that
in this way an irrevocable functional union takes place between muscles
which do not normally contract simultaneously. There thus occurs a condi-
tion which resembles the tics which in humans follow injury of this nerve,
and is characterized by an indiscriminate mass contraction whose propor-
tion varies as the amount of damage to the nerve. These contractions show
no tendency to regress, even over a three-year period. In man there is a
better expectation of being able to suppress or modify the tic movements
through reeducation.

Imitative Behavior in a Monkey

A case of what appears to be imitative behavior in a young rhesus monkey
has been studied by Dr. J. Ball. Being caged with a kitten for company,
this 11-month-old animal learned to drink liquids by lapping, copying per-
fectly the technique of its companion. The new method of drinking con-
tinued several months, as long as the animal lived. The normal way of
drinking and the one originally employed by this animal is a process of
sucking. Among 600 rhesus monkeys whose habits have been closely fol-
lowed in this laboratory, none have ever been observed to drink by lapping
in this open-mouthed fashion. Dr. Ball concludes that this case can be
interpreted as imitation.

Brain of the Whale

Another contribution to the structure of the brain of the whale has been
made by Dr. 0. R. Langworthy in collaboration with Dr. F. A. Ries. Be-
cause of its many interesting adaptations to the requirements of marine life,
Dr. Langworthy has made the whale brain the subject of several investiga-
tions, as the reader of these reports will know. The present investigation
includes eight additional brains of the sperm whale, Physeter catodon, mak-
ing Dr. Langworthy 's collection, now housed in the Department of Neurology
of the Johns Hopkins University, particularly adequate for such study.

Defective Brain Development

Dr. P. A. Fitz-Gerald of the Department of Anatomy, University College,
Dublin, while a guest of our laboratory during the past year has made a
study of the cerebral hemispheres of an eighth month child showing defec-
tive brain functioning. In the central and parietal regions the cortex of
this child, instead of being properly fissured, was found to be almost smooth,
and symmetrically so on the two sides. All the other cortical areas appeared
to be normal. Dr. Fitz-Gerald associates the stunting of sulcus formation
with a developmental arrest in cortical histogenesis and in this way he is
helping to solve the problem which has long confronted the embryologist,
of what is the exact nature of the forces that produce fissures and convolu-
tions on the brain surface. He is following his surface survey of the mate-
rial with a microscopic study of the tissues involved.

30 CARNEGIE INSTITUTION OF WASHINGTON

MORPHOLOGICAL STUDIES

Clavicles and Long Bones of the Limbs in Man and Apes

In order to obtain suitable data bearing upon variability and asymmetries
in higher primates and their comparison with man, Dr. A. H. Schultz has
collected measurements and observations on a total of 753 human skeletons
belonging to a variety of races, and a total of 530 simian skeletons belonging
to all the genera of anthropoid apes and to macaques. The data have been
obtained with the same technique and for the most part by himself and with
the primary intention of its use for the study of variability and asymmetry.
With it he has been able to make comparisons between some civilized and
uncivilized races of man and comparisons between man and other primates,
particularly the anthropoid apes. Heretofore we have had infinitely more
data on asymmetries and variation in man than in other animals. Dr.
Schultz has now provided the information regarding other related forms
which we needed for evaluation of the data which were already available for
man.

Among his observations on asymmetries he found, in comparing their dis-
tribution in man with that in apes and the macaque, that in general symmetry
is rarer in the former than in the latter and that preference of asymmetries
for one side is not nearly as marked in the apes as it is in man. In the
macaque asymmetries favor both sides with practically the same frequency.
In regard to asymmetries of the lower extremities man does not differ essen-
tially from the other primates. In all primates there is comparatively little
preference of one lower extremity over the other. Asymmetries in the lengths
of the clavicles favor both sides with practically equal frequency in gorilla
and chimpanzee and the right side slightly more frequently than the left in
orang-utan, gibbon, and the macaque. This contrasts strikingly with the
conditions in man, in whom there is a definite tendency for the left clavicles
to be longer. In all the human groups the lengths of the long bones of the arm
favor the right side in the great majority of cases, and the asymmetries of
the arms favoring the right side are more frequent in females than in males
among whites, Negroes, Eskimos, and Indians. Since Dr. Schultz had pre-
viously shown a similar prevalence of asymmetries in human fetuses, he con-
cludes that the common preferential use of the right arm in man cannot
be held responsible for its definite tendency to be longer. Nor is it likely
connected with "right-handedness" since "left-handedness" is much rarer in
man than are asymmetries favoring the left arms. Furthermore "left-
handedness" is regarded as hereditary, whereas asymmetries of the human
body are thought not to be.

In general the tables of Dr. Schultz demonstrate conclusively that man
differs strikingly from apes and monkeys in regard to both the percentage
distribution and the relative amount of asymmetries of the clavicles and
the long bones of the arms ; and that man and other primates are practically
alike in regard to the degree of asymmetries and the difference in the prefer-
ence of asymmetries for the two sides in the long bones of the legs.

DIVISION OF ANIMAL BIOLOGY 31

Vertebrae and Length of Spinal Regions in Primates

From observations made on 300 freshly killed catarrhine primates, with
measurements made from the centers of the intervertebral disks, Dr. Schultz
has been able to show that the cervical and the thoracic vertebrae are pro-
portionately larger in all higher primates than in the lower catarrhines, and
that among all primates man has the relatively longest cervical and thoracic
regions and the comparatively largest lumbar vertebrae. However, the com-
mon evolutionary trend among higher primates to reduce the number of
vertebrae and the relative length of the lumbar and caudal regions has gone
to greater extremes in some anthropoid apes than in man.

In a series of 80 adult gibbons, having a much greater vertebral variability
than man, it was found that a reduction in the number of thoraco-lumbar
vertebrae is not accompanied by a corresponding reduction in the relative
length of this region. On the other hand, a close correlation exists between
decreased numbers of thoraco-lumbar vertebrae and increased numbers of
sacral vertebrae. Less frequently the sacrum increases its number of vertebrae
at the expense of the coccygeal region.

As compared with the lower catarrhines, man and the anthropoid apes
differ not only in possessing fewer thoraco-lumbar and caudal vertebrae and
more sacral vertebrae but also in having comparatively longer cervical, thor-
acic, and sacral regions and much shorter lumbar regions.

Shoulder Architecture

In previous reports reference has been made to the studies of Mr. Brazier
Howell on the architecture of the shoulder in the vertebrate classes, including
Amphibia and Reptilia. To these may now be added studies on the shoulder
region of birds and therian Mammalia. In his description of the domestic
fowl Mr. Howell has made a contribution to comparative anatomy by the
interpretation of the avian shoulder in terms of the tetrapod animal. As in
his other studies, due emphasis has been given to innervation in all questions
of muscular homologies.

Among the noteworthy details pointed out by Mr. Howell are the follow-
ing: the spinal accessory nerve and its associated muscles are absent, being
replaced by a suboccipital group; m. levator scapulae is lacking; the rhom-
boids occur in two layers; the subscapularis is poorly represented, whereas
the dorsalis scapulae and deltoid are robust; the large breast muscle repre-
sents the pectoralis minor element, the major being small and deep; supra-
and infraspinati are absent; and the brachialis is a feeble muscle near the
elbow.

In the anatomy of the appendages Mr. Howell finds a large break between
those of the therian mammals and those of reptiles and even those of pro-
totherians. In fact he finds that the monotremes are more comparable with
reptiles than they are with therian mammals. For that reason he omits them
from his analysis of the mammalian shoulder. He accounts for the great
dissimilarity in the pectoral appendages of the above groups by the differ-
ences in the way the limbs are used. He points out the prone position of the
reptilian body and the horizontal position of the humerus, with divergent

32 CARNEGIE INSTITUTION OF WASHINGTON

elbows, features which call for a very different skeletal and muscular pro-
vision from that with which we are familiar in mammals. The reptilian type
of shoulder architecture is quite unsuited for quick movements and long-
sustained action. In order to change the reptilian into the mammalian plan
it was only necessary for reptiles to bring the elbow beneath the body. But
this required such complicated skeletal and muscular adjustments about the
shoulder joint that only a single reptilian group (Theriodontia) ever suc-
ceeded in its accomplishment. The improvement in function which resulted
from the invention of the mammalian plan of shoulder seems to have played
a large part in the development of the class Mammalia. The new deal pro-
vided the mammals with a means of using their limbs in a single plane, for
purposes of locomotion, and over extended periods with the expenditure of
much less energy. Over and above his interesting interpretations Mr.
Howell's study has brought together a large amount of information regard-
ing the shoulder region of mammals that will be of much value to the com-
parative anatomist.

Muscles of Hip and Thigh

The comparative anatomical studies which Mr. Brazier Howell has been
making on the shoulder girdle have been supplemented by a similar method
of analysis of architecture of the hip and thigh. His material includes the
domestic fowl, the giant Japanese salamander, the reptile Iguana, and many
varieties of mammals, a sufficient material for a comprehensive review of the
homologies of the pelvic girdle.

It is pointed out by Mr. Howell that though the pelvic and pectoral girdles
show many resemblances, yet the structures of neither pair can be properly
homologized with those of the other, because of their difference in derivation.
The cartilaginous pectoral girdle developed as an adjunct of the membranous
girdle and is really a part of the head and axial skeleton. When the limbs
became the primary organs of locomotion it was the pectoral limbs that pro-
pelled the animal by traction, and the girdle movement accompanying this
action was accomplished largely by sidewise movements of the head. The
membranous part of the girdle was derived from the posterior margin of the
gill basket, whose musculature (trapezius) contributed to the control of the
girdle. It had the complication of having a dual origin (membranous and
cartilaginous) added to the fact of its location at the anterior termination of
the axial musculature. With the pelvic girdle matters were quite different.
The latter was initiated without the influence of anchorage to the axial
skeleton, inasmuch as the pelvic appendages at first functioned for support
only and not propulsion. For a long time they remained free of the axial
skeleton, that is, from the viewpoint of the phylogenist. Furthermore the
influence of the body muscles upon the pelvis were quite different from that
upon the shoulder girdle. The story of the difference in functioning of the
pectoral and pelvic limbs in the progress of their assumption of more com-
plicated functions has been worked out in its significant details and Mr.
Howell has provided the anatomist with a rationale for this region which is
a definite advance over that heretofore available. With his four-group basis
as the chief criterion, he has been able in large part to homologize the pelvic

DIVISION OF ANIMAL BIOLOGY 33

muscles of urodeles, lacertilians, mammals, and birds. Even so there remain
some specializations which still obscure their precise relationships.

Visceral Anatomy of an Infant Chimpanzee

An infant female chimpanzee, 74 days old, which died of an acute pul-
monary infection, provided Dr. W. L. Straus, Jr., with an opportunity to study
the thoracic and abdominal regions at this early stage. The body was in-
jected with a 10 per cent formalin solution within one-half hour following
death, giving excellent preservation of the tissues. Anatomical data on the
viscera of this important primate are relatively scant and this appears to be
the youngest infant thus far systematically studied. The sitting height and
trunk height, measured after fixation, were 31.5 cm. and 16.8 cm., respectively.
On comparing this specimen with an older chimpanzee and with an infant
orang-utan Dr. Straus found that there are but small differences in visceral
morphology between the two chimpanzee specimens though there is a differ-
ence of nearly four years in their age, whereas the contrasts between the
infant chimpanzee and infant orang-utan are many and striking, an observa-
tion that will not surprise those who are genetically minded. Dr. Straus has
made his detailed descriptions and measurements available to other investi-
gators by formal publication.

Branches of the Aortic Arch in the Monkey

In Year Book No. 35 the investigations of Dr. C. F. De Garis on varia-
tions in the branches of the aortic arch in the macaque monkey were
referred to and at that time the value of having a large number of speci-
mens from a single species was pointed out. To his first series of 115 speci-
mens, he has now been able to add 153 more. This provides a total series
large enough for significant statistical treatment and for the consideration
of problems of variation, inheritance, and symmetry. The new material
when arranged in polygons of frequency further substantiates a norm having
a short truncus communis comparable to that often found in man. This
norm has a marked modal value which is intermediate between human and
mammalian patterns, with almost equal distribution of these patterns on
either side of the norm. The next step appears to be the search for correla-
tions of this norm with trunk measurements and visceral structure and the
consideration of the influences of body symmetry. This will inevitably lead
the investigator back into the fetal period, where a large part of the deter-
mination of the vascular pattern takes place.

Asiatic Primate Expedition

Joining forces with Professor H. J. Coolidge of Harvard University and
Dr. R. C. Carpenter of Columbia University, Dr. A. H. Schultz participated
in an expedition to northern Siam and British North Borneo in search of
anthropoid material that is native there, and particularly the gibbon and
orang-utan. Their program included comprehensive observations on the
behavior and social relations of entire ape families as they live in their
native jungles, and on the other hand the collection of skins, skeletons,

34 CARNEGIE INSTITUTION OF WASHINGTON

embryos, parasites, stomach contents, bodily measurements of the dead
animals with a view toward species characters, growth before and after
birth, variability, incidence of disease and injury, and any facts relating
to pregnancy. Through careful preparations for the expedition and through
the interest and assistance of the authorities of the countries which they
visited they were able to obtain data and specimens for subsequent study
at their home laboratories, in amount far beyond their expectations. From
his own standpoint the large collection of gibbon specimens that has thus
become available more than justifies the time and effort that Dr. Schultz
devoted to the undertaking. The skeletons are now being cleaned and
prepared for study.

Physiological Observations on Fireflies

As a collateral to his cytological studies on insects Dr. J. B. Buck pub-
lished during the past year his records on fireflies, an extensive collection
of which were obtained by him on a visit to Jamaica in the preceding year
while a fellow in the Zoological Laboratory of the Johns Hopkins Univer-
sity. In general he found that each species is rather definitely confined to a
particular altitudinal range. A few species were found in a single district
but most species are found in multiple regions where the altitude deter-
mines the appropriate temperature and moisture.

The observations by Dr. Buck on the spectral composition of the light
emitted by the fireflies are of especial interest. Under the spectroscope the
light emitted by all the species investigated produces a broad structureless
band lying wholly within the visible spectrum. In no case was the light
below 5050 or above 6550 Angstrom units. It is found that several species
emit light of the same spectral composition, whereas others differ from one
another. It is also noted that the spectra of some species present a rela-
tively extensive range, e.g. 5050 to 6450 Angstrom units. Finally, Dr. Buck
was able to demonstrate photographically that the apparently different color
of the light emitted by the thoracic and abdominal light organs in certain
species is due to an actual difference in the color and is not a subjective effect.

DIVISION OF ANIMAL BIOLOGY 35

DEPARTMENT OF GENETICS x

A. F. Blakeslee, Director

CHROMOSOME INVESTIGATIONS

A. F. Blakeslee, A. G. Avery, A. D. Bergner, S. Satina, H. E. Warmke, J. T.
Buchholz, J. L. Cartledge, and E. W. Sinnott

Last year we reported the discovery, which had just been made, that treat-
ment of seeds of Datura with the alkaloid colchicine would bring about
changes in structure of the seedlings which were interpreted as due to
doubling the number of their chromosomes. It was pointed out that if our
interpretation were correct and the methods could be used with other forms,
a tool of considerable value would be available both to the practical plant
breeder and to the plant geneticist interested in problems of evolution. The
present year's work has shown that induction of chromosome doubling by
chemical treatment is of wide application among flowering plants and enables
the investigator of certain problems to work with a measure of precision not
hitherto possible. The polyploid series In, 2n, 3n, and 4n have been secured
in Datura stramonium and may be expected in other species. At the be-
ginning of the calendar year Dr. H. E. Warmke joined our group and since
then has assisted in the polyploidy investigations which have been sup-
ported by a grant from the Carnegie Corporation to the Carnegie Institution
of Washington. The polyploidy project is a single phase of the chromosome
problem which has been occupying our group. Other phases of this larger
problem are not being neglected but it seems best to restrict the report
this year to a discussion of progress in the polyploidy project.

Methods of Inducing Chromosome Doubling by Treatment with

Colchicine

Soaking seeds in solutions of colchicine of different concentrations for
different species is the most convenient method of treatment. Seeds of
Portulaca respond to a concentration of 0.0002 per cent for two days by
producing seedlings with swollen stems. Seed treatment with 0.4 and 0.8
per cent solutions for 4 to 8 days has been found well adapted to Datura and
induces an abundant production of 4n branches. The effect of the drug
is first noted in delaying germination and development. When the treat-
ment is severe the stems of the seedlings are strongly swollen and many
fail to develop beyond the cotyledon stage. The leaves of affected plants
are characteristically roughened owing to the fact that they contain a
mixture of 2n and 4n cells. From these "mixochimeras" there ultimately
may grow out branches with smooth leaves which either are normal 2n
or contain twice the normal number of chromosomes and are therefore 4n.
The 4n flowers may be recognized by the larger size of their pollen grains or
by the more tedious method of actually counting the chromosomes in young
buds which have been fixed and stained by the acetocarmine method.

In addition to the seeds, vegetative parts of the plant may be treated by
a variety of methods. The most successful method consists in spraying
growing points with solutions or better with emulsions containing colchicine.
To our surprise, injecting solutions and allowing solutions to be soaked up
through the cut parts of the stem were not successful.

1 Address: Cold Spring Harbor, Long Island, New York.

CARNEGIE INSTITUTION OF WASHINGTON

Species in Which Chromosome Doubling Has Been Induced

One of the early problems in the use of colchicine was the extent to which
this drug would be effective in doubling the chromosome number of other
forms than Datura. A number of species were selected for testing because
of their adaptability to experimental cultivation or because of their relation
to special problems involved in polyploidy. Following is a list of species of
flowering plants in which at least flowers with doubled chromosome number
have been secured through colchicine treatment.

Plants with Chromosomes Doubled by Colchicine Treatment

Those marked * have yielded An seed; those marked ** have given An offspring in
second generation; unmarked plants were shown to have An tissue by flowers with
50 per cent or more 2n pollen grains.

Caryophyllace^e
Lychnis dioica**
Stellaria media**
Vaccaria parviflora *

CHENOPODIACEiE

Spinacia oleracea **
Composite

Bidens leucantha **

Cosmos sulphureus **

Rudbeckia hirta
Crucifer^e

Raphanus sativa *

CUCURBITACE^

Cucurbita pepo

Mammoth pumpkin

Pear gourd

Small round china gourd*

"Spoon" gourd*

White sphere squash *

Yellow disk squash*

Straight-neck yellow squash *
Cucurbita maxima

Blue Hubbard squash*

Warren Essex squash *

Buttercup squash*
Cucurbita moschata

Small yellow cushaw squash *
Cucurbita maxima X C. moschata *
Lagenaria vulgaris

Dipper gourd

Giant bottle gourd*

Knobkerrie gourd *

Hercules Club gourd *

EUPHORBIACE.E

Mercurialis annua
Malvaceae
Anoda lavateroides

Morace^e

Cannabis sativa**
Humulus japonicus

OxALIDACE^E

Oxalis valdiviensis **
Plantaginace^
Plantago lanceolata

POLEMONIACE.E

Collomia coccinea *
Gilia abrothanifolia

PORTULACACE^E

Portulaca grand iflora **
Portulaca marginata **
Portulaca oleracese **
Portulaca parana **

SOLANACE.E

Datura ceratocaula **
Datura discolor
Datura ferox**
Datura innoxia
Datura leichhardtii **
Datura metel **
Datura meteloides
Datura pruinosa
Datura quercifolia *
Datura stramonium**
6 main lines and gene types *
8 races with extra chromosomal
material *
Lycopersicum esculentum *
Nicotiana sanderae **
Nicotiana tabacum X N. glutinosa **
Nicotiana glutinosa X N. sylvestris *
Petunia axillaris**
Violace^e

Viola tricolor, hortensis

DIVISION OF ANIMAL BIOLOGY 37

The 65 different kinds of plants shown in the list above have all been
induced to double their chromosome numbers by treatment with colchicine.
They represent 14 different families, 24 genera, and 41 species. Among
them are 3 species hybrids.

The species successfully treated represent a considerable number of genera
and families, enough to indicate that the method is of wide application. In
addition, a number of forms which showed the vegetative peculiarities
characteristic of tissue with doubled chromosome number following colchi-
cine treatment were discarded for various reasons before the special treat-
ment required to force out 4n branches had been developed. This was
notably true of the grass family, but other investigators who have specialized
on this family have recently been successful in securing 4n races of grasses
through treatment with colchicine. The fungi seem highly resistant to the
toxic action of colchicine. Miss Satina has treated a representative group
of fungi with saturated solutions of colchicine (±4.0 per cent) with no
obvious effect. She has succeeded, however, in doubling the chromosome
number of Marchantia polymorpha by treating the gemmae with colchicine
and has thus secured 2n male and female thalli of this liverwort.

Polyploidy in Datura

Most intensive study has been made of the responses of the 10 herbaceous
species of Datura to colchicine treatment. All appear to have their divid-
ing chromosomes affected in such a way that cells with doubled and higher
number of chromosomes result. D. ceratocaula is especially sensitive and
is readily induced to double its chromosome number when treated by spray-
ing with solutions of colchicine, a method not very effective with other
Daturas. Certain races of D. metel appear to be somewhat resistant. Treat-
ment of 4n seeds of D. stramonium has given rise to branches with 8n
flowers, as has also severe treatment of 2n seeds. Such octoploid flowers
have so far failed to produce seed. Hexaploid (6n) flowers have been secured
by spraying growing points of 3n plants. A few large seeds from such 6n
flowers have been formed but they have not yet been brought to germination.

Haploid (In) plants appear not infrequently in our cultures through
parthenogenesis of the reduced egg cells. Though some haploids produce
very small capsules and an occasional seed, others are entirely sterile and
cannot be induced to set any fruits. By spraying branches of a haploid
with colchicine solutions it has been found possible to induce In cells in the
buds to double their chromosomes and thus to become 2n. An abundant
production of large capsules with 2n seeds results. Methods are being in-
vestigated which it is hoped may be effective in inducing In offspring from
2n parents. If they prove successful, simple means would be available of
producing homozygous races from highly heterozygous parents (such as
species hybrids) through the induction of In seedlings which may be forced
to produce normal 2n capsules through chromosome doubling.

Dr. Bergner has been making a study of the chromosomal condition in ab-
normal branches on plants from seeds treated with colchicine. Chromosomal
deficiencies due apparently to elimination of lagging chromosomes during

38 CARNEGIE INSTITUTION OF WASHINGTON

the process of doubling appear to be common. Branches have been identified
which lacked from one to six chromosomes but were otherwise 4n. There
is suggestion that periclinal chimeras may be present. These findings show
that the immediate result of colchicine treatment cannot be depended upon
to be balanced 4w tissue with four of each kind of chromosomes present.
They furnish added justification for our rule that 4n plants for critical study
should only be used from the second generation and not then until cytological
study has demonstrated that each of the n sets has four chromosomes. Before
another report we expect to have such pure 4n plants for all the 10 herba-
ceous Daturas as well as Zn individuals and these will be kept in cultivation
by grafts and cuttings. Already we have gotten 4n flowers and seeds from
14 different lines of Datura stramonium which we wished to use as tetra-
ploids for special purposes. Among these are a half-dozen pure breeders
with extra chromosomal material which we wished to use in cooperative
studies with Dr. Sinnott on anatomical effects of polyploidy.

Double Diploidy

A well-established method of evolution both of cultivated plants and of
plant species in nature is through the spontaneous doubling of the chromo-
some number of sterile hybrids between species. Such species hybrids are
sterile because the chromosomes of the one parental species are too distantly
related to those of the other species to allow the chromosomes to pair, and
pairing is necessary for sexual reproduction. When the chromosomes in the
hybrid are doubled in number the chromosomes of each species will find
duplicates with which to pair and the hybrid will become fertile. It seemed
desirable to see if such formation of new species could be induced by labora-
tory methods. Through the kindness of Dr. F. 0. Holmes material was
secured of the species hybrid Nicotiana tabacum X N. glutinosa. This is
completely sterile. By treating the hybrid plants with colchicine, fertile
flowers have been induced which have produced an abundance of double
diploid seed, and by the germination of the latter a double diploid race or
new species has been established.

Effects of Polyploidy

Now that a ready method of doubling chromosomes is available, it is
possible to learn the effects of the doubled number upon the morphology
and physiology of the plants affected. Conclusions regarding the effects
of polyploidy have heretofore been too often drawn from polyploids found in
nature in which the effects of polyploidy alone could not be easily separated
from those due to genes which differed in the two members of the poly-
ploid series compared. In consequence conclusions regarding polyploids
have often been conflicting.

Since doubling chromosome number appears to have been a method of
evolution in nature it is of importance to learn the effect of this process
upon the sex mechanism in plants in which the sexes are separate. Evidence
from related species in nature has been interpreted as signifying that
doubling the chromosome number of a dioecious species gives rise to a
hermaphroditic form. Other investigators believe that the chromosomal

DIVISION OF ANIMAL BIOLOGY 39

mechanism would necessarily work against the establishing of either a
hermaphroditic or a purely dioecious race by chromosome doubling. A
study is being made of a series of dioecious species some of which are listed
above as having had their chromosome number doubled. For such forms
we should soon be able to learn the effect of polyploidy on the sex mechanism.

Another problem under investigation is the effect of polyploidy upon
self-sterility, which is common among plants. A number of self-sterile
species are being tested. In one case at least, preliminary tests seem to
indicate that doubling the chromosome number neither increases nor de-
creases the degree of self-sterility.

In 1934 there were published by the Carnegie Institution the results
of a cooperative study with Dr. Sinnott on the anatomy of extra chromo-
somal types in Datura stramonium. Differences in number and size of
cells and in tissue pattern were demonstrated for 2n+l types and also for
the balanced polyploid series, In, 2n, 3n, and 4n. It is still unclear how the
qualitative differences are brought about between the members of the poly-
ploid series. It is proposed to investigate this problem further than was
possible in the preliminary study and to include a larger range of anatomical
characters in all the herbaceous species of Datura. The possible antagonism
between the influence of doubled chromosome number and the presence
of unbalanced extra chromosomal material for which races are being
developed by colchicine treatment will be investigated. It is thought that
the qualitative effects of polyploids may be due to a differential effect of
doubling upon different chromosomes. The effect of polyploidy upon size,
shape, and growth rates can be better studied in some ways in fruits of the
Cucurbitaceae, a group in which Sinnott has carried on investigations for
many years and in which highly inbred lines are available. As shown in
the list above, the chromosome number has been doubled in a considerable
number of Sinnott's squashes and gourds, so that tetraploids of these
races should be ready for detailed study by next season.

Attempts to Double Chromosome Number in Animals by Colchicine

Treatment

In cooperation with Dr. G. C. Embody and with the assistance of A. M.
Phillips, attempts were made by the use of colchicine to induce tetraploidy
in trout by treatment of eggs with the hope that the fusion nucleus could
be induced to double its chromosomes before the first division. In co-
operation with Dr. G. K. Noble and with the assistance of J. A. Mathewson,
eggs also of frogs (Rana pipiens and R. sylvatica) and eggs of a number of
aquarium fishes were treated with colchicine. In all these experiments
difficulties were encountered in getting the drug to penetrate the membranes
and in consequence the attempts to induce tetraploids in these animals were
unsuccessful. It is possible that eggs which develop outside the body are
better protected against unfavorable environmental influences than those
which develop within the body. In consequence the latter might be more
promising material in which to attempt chromosome doubling despite the
technical difficulties involved in handling eggs of such species.

40 CARNEGIE INSTITUTION OF WASHINGTON

Tests with Other Chemicals

By the use of Portulaca seedlings which show swellings of the stem due
to tetraploidy when the seeds are treated with colchicine, a series of experi-
ments were started in cooperation with Dr. Roger Adams to determine if
possible what specific groupings of the colchicine molecule are necessary
for the action of this chemical in doubling chromosome number. The
following results were obtained with chemicals supplied by Dr. Adams:

Colchiceine — no effect

Trimethylcolchicinic acid hydrochloride — no effect

N-Acetyliodocolchinol — no effect

N-Acetylcolchinol — no effect

Benzoyl colchiceine — no effect

Colchicine salicylate — same reaction as colchicine

It is concluded that probably any modification of the colchicine molecule,
even minor in character, causes the disappearance of its activity in doubling
the number of chromosomes.

An attempt has been made to find other chemicals which would double
chromosome number. A few have been found to react positively to the
Portulaca test and to induce doubling in some of the cells, but none are
as effective as colchicine. Sodium cacodylate, for example, induces a
positive reaction with Portulaca and has induced in flowers in this species,
but it is ineffective with Datura.

Work is under way on other problems which have to do with control
of genetic behavior and with a better understanding of the nature and
effects of polyploidy, especially as it relates to evolution in nature, but an
account of these experiments is deferred to next year's report.

THE GENE
M. Demerec, B. P. Kaufmann, and Margaret E. Hoover

The Nature of X-Ray Induced Changes

During the past year a cooperative study by H. Bauer, M. Demerec, and
B. P. Kaufmann on chromosomal alterations induced by X-rays in Drosophila
melanog aster was completed and the data were analyzed. The work con-
sisted of an analysis of salivary gland chromosomes of first generation larvae
obtained by mating untreated females with X-rayed males. The chromo-
some rearrangements which were studied in this experiment were those in-
duced in the treated sperm and not eliminated during the embryonic and
early larval development, since glands were selected for cytological study
from larvae preparing to pupate. Experiments to be described later show
that the death rate in these early stages of the life cycle is high. It is prob-
able that non-viable chromosomal combinations are responsible to a large
extent for that high death rate. In cytological analysis of salivary gland
chromosomes we are dealing, therefore, with the surviving members of a
much larger population. Permanent preparations of 1765 pairs of salivary
glands were used and a total of 1038 chromosome breaks were analyzed.
The X-ray radiation was applied by a Universal Type Coolidge tube, with

DIVISION OF ANIMAL BIOLOGY

a tungsten target, at 85 kilovolts and 7 milliamperes, the dosage being meas-
ured by a Fricke-Glasser dosimeter.

The relation between the dosage and the frequency of breaks is shown in
the accompanying table.

Dosage

Sperm

Breaks per

r-units

Total

Number with
alterations

Per cent with
alterations

Total sperm
(per cent)

Changed sperm
(per cent)

1000

2000

3000

4000

5000

331

277
725
215
217

193

3 . 63 + 1 . 03

8.66 + 1.69

26 . 62 + 1 . 64

29.8 +3.12

40.09+3.33

8.16 + 0.02

22.02+0.05

72.00 + 0.05

85.58 + 0.11

125.35±0.12

2.25 + 0.13
2.54 + 0.18
2.70 + 0.09
2.88 + 0.18
3.13 + 0.16

It is clear from these data that there is no simple relationship between
dosage and percentage of breaks per total sperm (fig. 1) . The effect observed
here is not directly proportional to the dosage, and this relationship is dif-
ferent from that observed in the case of lethal changes where the effect was
found to be proportional to dosage. In this case the observed curve at low
dosages (1000 and 2000 r-units) fits closely an exponential square curve,
while at high dosages the deviation from it is appreciable. For its whole
length the observed curve approximates an exponential 1.5 power curve
which is intermediate between the first power of dosage curve and the square
power curve. A similar relationship has recently been reported by Sax for
chromosomal aberrations in Tradescantia and by Muller for genetically de-
tected aberrations in Drosophila. Direct proportionality to dosage indi-
cates that individual changes are induced by single ionizations, while a
square power relationship would be expected, at least at dosage levels in
which there is a low number of breaks per nucleus, if an individual change,
in this case a chromosomal rearrangement, were caused by two independent
ionizations.

Two types of regions can be distinguished in salivary gland chromosomes
as well as in mitotic chromosomes of D. melanog aster, namely, euchro-
matic regions and heterochromatic regions. Heterochromatic segments are
located in each chromosome near the spindle fiber attachment point and in
salivary gland nuclei they come together into what is known as the chromo-
center. In proportion to the total length, heterochromatic regions are ap-
preciably longer in metaphase chromosomes than in salivary gland chromo-
somes. The study of 1038 breaks showed that they are distributed at random
throughout the euchromatic regions, with the possible exception of distal
sections, where breaks tend to be slightly more frequent. On the other hand,
in heterochromatic regions of salivary chromosomes breaks were found to
be much more frequent than in euchromatic regions of similar lengths. How-
ever, the frequency of breaks is found to be approximately proportional to
the length of heterochromatic region as represented in metaphase chromo-
somes. This finding was discussed in last year's report (Year Book No. 36)
and used as evidence to support the hypothesis that breaks are distributed

CARNEGIE INSTITUTION OF WASHINGTON

at random per unit length of chromonema, that the chromonema is struc-
turally similar in all chromosomes, and that it may be looked upon as com-
posed of fundamental units or backbones corresponding to the fiber protein
molecule pictured by W. T. Astbury. The study of breaks showed also
that they are distributed at random among chromosomes of comparable
lengths. The analysis of two break cases indicates that these breaks are
independent of each other, suggesting that a different mechanism is re-

160 -
150
140
130

*I20

100
u.
o

S80

g70
o
or

4d 60
Ql

50
40
30
20
10

Observed

Expected -

Ist Power

1.5 Power

2nd Power

1000

2000

Dosage

3000

in r units

Sobo

Fig. 1. Percentage of induced chromosome breaks in the total sperm. Curves show observed

and theoretical values at different dosages.

sponsible for reattachments producing induced inversions and translocations
than for those connected with crossing-over, where it is known that the posi-
tion of the second break is influenced by the position of the first break.

The origin of induced chromosomal rearrangements may be accounted for
by either of two mechanisms, namely, that a break in the chromosome occurs
first and reattachment is accomplished later (Stadler) , or that breakage and
reunion are part of one process and occur simultaneously (Serebrovsky) .
The latter hypothesis assumes all regions involved in rearrangements to be

DIVISION OF ANIMAL BIOLOGY 43

in contact at the time the reunions occur. In order to account for the re-
arrangements observed in our experiment it would be necessary to assume
that in almost 20 per cent of cases more than two chromosome threads were
in contact at one point, and to explain some of the complex rearrangements
it would be necessary to assume that as many as six or eight threads were
in contact at one point. The improbability of this condition combined with
our analysis of the relationship between dosage and the percentage of breaks
suggests strongly that X-ray induced chromosomal rearrangements result
from such a breakage and reattachment mechanism as Stadler has proposed.

The cytogenetic analysis of the white-facet region of D. melanogaster was
continued this year by Demerec and Hoover. A contribution to this study
was previously made by Helen Slizynska (Year Book No. 36). With an
X-ray treatment of approximately 2500 r-units, 81 separate changes have
been induced so far in this region of the X-chromosome. Of these, 54 have
been completely analyzed both cytologically and genetically at the time this
report is made. These changes may be placed in three groupings, according
to their genetic effect, namely, (1) changes that are viable, (2) changes that
are lethal in the homozygous or hemizygous condition, and (3) changes re-
sulting in a mottled phenotype.

The viable changes, owing to the method of detection, are all connected
with the white locus. Out of a total of 25 such mutant whites, none was
found to be connected with a major chromosomal aberration such as a trans-
location or inversion. Eight of these were studied for the presence of all
critical bands and no deficiencies were detected in any. This finding indi-
cates that at least the majority of viable changes are free from chromosomal
aberrations and are not associated with minute deficiencies.

In the second group 28 lethal changes have been analyzed; 7 of these were
found to be connected with chromosome changes and 21 were free from any
rearrangement. This proportion suggests that a majority of lethal changes
induced by this treatment are not associated with chromosomal aberrations
and, consequently, must originate independently of the chromosome breaks
resulting in inversions and translocations. These 21 lethals were subjected
to careful salivary gland chromosome analysis. In 2 cases no known bands
were absent, but 19 were found to be cytologically detectable deficiencies.
Five of the 7 lethals associated with chromosomal rearrangements have been
studied so far ; 3 are not deficiencies and 2 are deficiencies.

The changes producing a mottled phenotype form a separate class. The
23 such changes collected so far have all been associated with chromosomal
rearrangements. Of these, 13 have been studied for deficiencies and in only
one case was such a deficiency detectable.

These results suggest that the majority of viable changes in the white
locus are free from association with chromosomal aberrations and are also
probably not gene deficiencies; that a high proportion of lethal changes
are also free from chromosomal aberrations, but the great majority of these
are cytologically detectable deficiencies. On the other hand, of those lethals
connected with rearrangements, the minority may be deficiencies. The dif-
ference in this proportion may possibly be accounted for by position effect.
All mottleds so far obtained are associated with chromosomal changes and

44 CARNEGIE INSTITUTION OF WASHINGTON

a great proportion of these are not deficiencies. All the chromosomal aber-
rations studied in relation to mottling have involved chromocentral regions.
The chromocenters of all the chromosomes seem effective in somehow pro-
ducing these mosaics. Three cases where rearrangements involving chromo-
centers have been detected have not shown this spotting, suggesting either that
all portions of the chromocentral regions are not equally effective, or that
some sort of differential position effect is involved.

It is interesting to note that the size of the deficiencies in this collection
cover a fairly large range from single up to 46 bands. In the size range from
12 to 46 bands, the distribution seems at random, whereas there is a piling
up of deficiencies of 1 to 4 bands. Out of 23 deficiencies analyzed, 13 were
small, 5 of these being single bands. The other 10 were scattered over the
larger size range. The study on distribution of breaks in chromosomes
reported above shows that chromosome breaks occur at random and that
they are independent of each other. Therefore, if deficiencies are caused
by two independent breaks and loss of a piece between them, it would be
expected that various sizes would occur with equal frequency. The data
collected so far indicate that this holds true for deficiencies involving 12 or
more bands but that it does not hold true for small deficiencies involving
1 to 4 bands. This suggests that these two classes of deficiencies were dif-
ferently induced, large deficiencies by two independent changes or ioniza-
tions and small deficiencies by a single ionization.

Response of Hereditary Material to X-Ray Treatment

In last year's report (Year Book No. 36) data were presented showing
that lethal changes induced in males by simultaneous treatments with X-rays
were consistently almost twice as frequent in flies of the Swedish-b stock as
in flies of the Oregon-R stock. It has been concluded that a biological factor
was responsible for this difference in the effect of X-rays on the hereditary
material. To investigate this problem further, another set of experiments
was conducted in which the frequency of dominant lethals was studied.
Males of Swedish-b and Oregon-R stocks were simultaneously treated with
1000, 2000, 3000, 4000, and 5000 r-units. They were mated to untreated
females and the frequency of dominant lethals was found by determining
the death rate during ontogeny. It has been observed that the frequency of
dominant lethals is higher in the treated Oregon-R series than in the simul-
taneously treated Swedish-b series. In the case of dominant lethals, there-
fore, the behavior of these two stocks is just opposite to the behavior ob-
served for sex linked lethals. This can be accounted for by either of the
following hypotheses: (1) Dominant and recessive lethals are basically
similar changes differing mainly in the degree of effect. The Oregon-R stock,
when compared with the Swedish-b stock, is physiologically more sensitive
to changes induced by X-ray treatment, and because of that sensitivity a
greater proportion of individuals carrying these changes die early in onto-
geny, the stock, therefore, showing a higher rate of dominant lethals and a
lower rate of recessive lethals. (2) Dominant lethals and recessive lethals
are, as far as the mechanism of origin is concerned, two unrelated types of
changes ; dominant lethals, for example, may be nonviable chromosomal aber-

DIVISION OF ANIMAL BIOLOGY 45

rations while recessive lethals may be mutant types. Then the difference
in the behavior of the two stocks may be accounted for by the presence of
some biological factor which makes one stock more sensitive to one type of
changes and the other stock more sensitive to the other type. In that case,
two factors may be responsible for the increased sensitivity. It may be that,
owing to a specific genetic constitution, chromosomes are more susceptible to
breakages and genes to changes. A parallel case is on record regarding spon-
taneous mutations which were increased by the presence of a certain gene
(Year Book No. 35). Or it may well be that this sensitivity is nothing else
but an expression of a physiological condition determining the survival rate
of various changes. In that case, the higher sensitivity of the Swedish-b stock
to lethal changes would mean that owing to a physiological state certain
changes which would be semi-lethal in Oregon-R stock are completely lethal
in Swedish-b.

In the Oregon-R stock a 1000 r-unit treatment induced about 22 per cent
of dominant lethals, a 3000 r treatment induced 63 per cent, and a 5000 r
treatment, 78 per cent. This shows that a very large proportion of induced
changes are being eliminated as dominant lethals. Since many of these are
undoubtedly connected with chromosomal aberrations, this evidence indicates
that probably a large proportion of these aberrations were eliminated before
the stage at which the material was taken for the salivary gland chromosome
study described earlier in this report.

Cytological Analysis of Induced Chromosomal Changes

An analysis of the numerous salivary glands of male and female larval de-
scendants of irradiated fathers used in the study of break frequency and
distribution has permitted diagnosis of various types of chromosomal altera-
tions. These include deficiencies, duplications, inversions, inter- and intra-
chromosomal translocations, and complex rearrangements involving two
or more chromosomes. As many as 13 breaks per treated sperm have been
detected. In one rearrangement involving 10 breaks, 2 bound an inverted
section ; the other 8 are included in a mutual exchange. About 1 per cent of
the rearrangements contained duplicated sections, indicating that the chromo-
somes of the sperm were longitudinally double at the time of recombination
of broken sections. One of these duplications, described by Kaufmann and
Bate, is intercalary in the left limb of the third chromosome, and is arranged
in the pattern of a "reversed repeat," as may be indicated by the sequence
ahcdgfeefghijk. Origin of the duplicated section is attributed to fusion of sister
chromatids at the same level, thus: abcd|efg|hijk giving ahcdgfeefghijk

abcd|efg|hijk
and probably another strand of the constitution abcdhijk, whose fate re-
mains conjectural. Union of sister chromatids in the manner here indicated
offers a possible explanation of the origin in nature of such reversed repeats
as occur in the chromosomes of Drosophila. In another duplication Kauf-
mann found that both chromatids of the right limb of the second chromosome
had been broken at one level but that a third break occurred at different
levels in each of the two strands. Although it cannot be determined with
certainty from this case that the second chromosome was split at the time

46 CARNEGIE INSTITUTION OF WASHINGTON

of irradiation, the rearrangement suggests the possibility that two strands
may be broken at the same level by the secondary effects of a single ionization.

A considerable number of alterations showed transfer of the nucleolus from
its normal chromocentral position to euchromatic regions of various chromo-
somes. From the pairing configurations in the salivary glands of individuals
heterozygous for such exchanges it could be determined that the nucleolus-
forming regions exist in the heterochromatic regions of the X- and Y-chromo-
somes, as had previously been described for mitotic chromosomes. In the
X-chromosome the nucleolus is found between the 20B1-2 and 20C1-2 bands.

A cytogenetic study of nine inversions in the X-chromosome was com-
pleted by Margaret E. Hoover. These inversions, differing in size and posi-
tion, were studied with particular attention to their cytological limits as
determined in the salivary gland chromosomes. The inversions selected
included four already familiar to Drosophila workers, namely, C1B, AM,
dl-49 and Dichsete. In addition, an X-ray induced transposition (303-1)
was used, three induced inversions associated with the cut locus, and the
tandem inversion (268-13) mentioned in last year's report. Crossing-over
data showed, as expected, that single crossovers are eliminated within in-
verted regions and greatly reduced in adjacent sections. Data on the amount
of synapsis undergone in the salivary gland chromosomes carrying inver-
sions indicate that even with these configurations a high degree of pairing is
maintained. Even at the breakage points complete synapsis was observed
very frequently. Eased on 100 random observations, the lowest value for
total synapsis through the inversion point was 48 per cent, the highest, 82 per
cent. Disregarding lack of pairing for less than 1 to 1 section at these in-
version points, the general aspect of the whole chromosome showed complete
synapsis in 67 to 86 per cent of cases as compared with 90 per cent for con-
trols. The relatively high frequency of synapsis in chromosomes carrying
inversions is thus indicated, suggesting that synapsis occurs in the early
stages of salivary gland development, when the thinner chromosomes would
encounter less difficulties than the mature chromosomes in forming the in-
version loops. The breakage points of the inversions were determined
cytologically by salivary gland chromosome analysis. In all, 20 breakage
points were studied. At 5 of these breakages, deficiencies were detected, at
13 no deficiencies were visible, and a single band at each of the other 2
remains unanalyzed. Those inversions in which the deficiencies were de-
tected are also associated with lethals, but 303-1, a semi-lethal, and Dichsete
and C1B, both lethal when homozygous, appear to be free from deficiencies.
This would indicate that genetic-physiological lethals and cytological de-
ficiencies are not necessarily synonymous.

In order to determine the nature of chromosomal alterations in cell genera-
tions immediately following radiation, J. G. Carlson, a guest investigator,
treated embryos of the grasshopper, Chortophaga viridifasciata, and studied
the mitoses in neuroblast and ganglion cells. Chromosomes which were
treated in stages between telophase and mid-prophase show, in succeeding
phases of the same mitotic cycle, chromosome fragmentation and transloca-
tion, chromatid breakage and translocation, and what may be half-chromatid
effects. The presence of chromatin bridges at anaphase appears to result

DIVISION OF ANIMAL BIOLOGY 47

from any of three different alterations: (1) chromosome translocation, (2)
chromatid translocation, (3) fusion of sister chromatids of the proximal por-
tions of fragmented chromosomes at their broken ends. The formation of
such bridges and the persistence of broken ends from one generation to the
next through breakage in late anaphase makes possible delayed attachments
following irradiation.

The mitotic behavior of some fragments lacking spindle attachments
parallels that of unaltered chromosomes in several respects. Such fragments
lie in the equatorial plane at metaphase. Their "chromatids" begin to sep-
arate at anaphase at almost the same time as do those of the unaltered
chromosomes, and they come into intimate contact with the spindle at
middle anaphase. Sister "chromatid" fragments usually move toward
opposite poles behind the other chromosomes, and so are included at telo-
phase in different daughter cells. The initial separation of "chromatids"
of fragments has the form of V's, rings, and pairs of rods. A hypothesis,
based on the assumption that broken ends of sister chromatids tend to fuse
inter se, is suggested to account for this. Not infrequently fragments are
included at telophase in the newly formed cell nucleus. This behavior has
a bearing on certain hypotheses of the mechanism of mitosis and on the
question of delayed attachments.

EXPERIMENTAL LEUKEMIA

E. C. MacDowell, J. S. Potter. M. N. Richter, J. Victor, M. Bovarnick, M. J. Taylor,
E. N. Ward, T. Laanes, and M. P. Wintersteiner

The cooperation of the College of Physicians and Surgeons of Columbia
University with the Department of Genetics, which has made possible the
establishment and continued progress of the leukemia project, has been
broadened this year by the active participation of the Department of Bio-
chemistry as well as the Department of Pathology.

Students of cancer have found that procedures that induce resistance to
transplanted tumors of various types have failed to influence spontaneous
tumors and they have largely abandoned the search for methods of inducing
resistance to spontaneous tumors as a result of the current belief that the
unique relationship between an animal and its own tumor cells makes the
induction of resistance to these cells impossible. But this belief has been
contradicted in the case of mouse leukemia (Year Book No. 35, p. 52) by
the demonstration that parallel results are due not to the unique relationship
between a mouse and its own leukemic cells but to immunological differences
between leukemic cells in spontaneous cases and those carried through long
series of transfers from mouse to mouse. Different cells require different
conditions for survival or suppression.

From this point one procedure would be to search directly by the method
of trial and error for conditions that would suppress spontaneous leukemic
cells; another procedure would be to determine (1) the nature of the mecha-
nisms of the successfully induced resistance to the long-transplanted cells,
and (2) the basis of the change in leukemic cells during the course of trans-
fer. With this knowledge it would be possible to proceed intelligently to
build up conditions to suppress spontaneous leukemic cells. The first or

48 CARNEGIE INSTITUTION OF WASHINGTON

direct approach has been followed unfruitfully by numberless workers; the
second or indirect approach represents direct contribution to the major aim
of the Institution workers of this group, namely, an understanding of normal
life processes as revealed by comparison with their abnormal functioning.
Indeed the nature of the evolution of leukemic cells of the spontaneous
type into the types found in the various transfer lines stands out as a primary
problem both for its own broad significance and as a lead to the nature of
the antecedent change of normal cells into spontaneous leukemic cells.

Passive Transfer of Immunity

Certain transplantable tumors are said to induce resistance to themselves.
Similarly for several years we have been consistently producing resistance
to lethal doses of transplanted leukemic cells by means of sublethal doses
of the same cells (Year Book No. 34, p. 45). This year the generality of
this phenomenon has been broadened by experiments with still another line
of leukemic cells. Such immunity seems to parallel that obtained by anti-
gens and antibodies of conventional immunology, but the very general
failure to obtain passive transfer of any tumor-induced immunity has made
the identification of antibodies impossible, and leaves a question as to the
nature of this induced resistance. During the year actively induced resist-
ance to leukemic cells has been passively transferred to susceptible mice
with success in 246 cases in 18 independent experiments with controls, in
every experiment, on the lethality of the dose of leukemic cells in the
absence of treatment. As in the studies on tumors, serum was ineffective;
but immediate protection was afforded by the use of saline suspensions of
minced tissue from actively immunized mice. The immediacy of the pro-
tection was emphasized by its effectiveness even when the immune tissue
was given one to three hours after the lethal dose of leukemic cells. This
is probably the first time that any type of induced resistance has completely
suppressed a neoplastic growth transplanted before the protecting treatment
was given. These results do not prove that an antibody, as usually under-
stood, is concerned, since living cells are present. The protection, however,
is not due to the living cells as such, for genetically identical living cells
from non-immunized mice give no protection. Passive immunization is
usually demonstrated by cell-free extracts. In this case the demonstration
depends upon the elimination of any form of active resistance by the im-
mediacy of the protection.

The passive transfer of immunity provides a short cut in the technique
of active immunization, as well as a new test for the development of active
immunity. The process of actively immunizing a large number of mice
has required many weeks and the initial steps have given uncertain results
on account of the difficulty of controlling dilutions as great as 10 ~~6 of the
standard dose. The actual number of cells from the same suspension given
to different mice may vary to the extent of killing some while others may not
be given enough cells to induce any active resistance, and therefore die from
the next higher dose. In such critical thresholds slight variations in the
condition of the leukemic cells or of the hosts may have deciding influence.
All these difficulties are avoided by starting with one treatment with im-

DIVISION OF ANIMAL BIOLOGY 49

mune tissue. The usual lethal test dose (1/64 of the standard dose) is at
once resisted by all mice and rapidly repeated massive doses build up the
strength of the active immunity.

The process of building up active immunity has been studied by succes-
sive tests for passive transfer. After each step, tissue was transferred to
still other hosts, which were then given the lethal test dose of leukemic
cells. Tissue from a mouse treated only with immune tissue gives no pro-
tection; after the first leukemic dose, the tissue will protect some of the
test mice; after two leukemic doses, the tissues will protect most of the
test mice; while after three doses, the tissue will protect practically all the
test mice. The production at a given date of any given number of mice
actively immunized by leukemic cells is no longer a difficulty.

A Chemical Approach

A possible lead for a chemical analysis and a clue to the difficulty of obtain-
ing non-cellular substances that resist neoplastic growth have been found
in the amazing ease with which the effectiveness of this supposed substance
can be destroyed mechanically. The method is simply to force the saline
suspension of minced tissue out of a syringe held firmly against the bottom
of the vessel. This process almost immediately reduces all discrete bits
of the tissue (liver) and in a very few minutes all cells are torn to pieces.
Is the protecting substance denatured by the same pressures that destroy
the cells, or is it so closely associated with cell structure (possibly as a modi-
fication of some normal cell constituent) that cell destruction is responsible
for the inactivation? When injected into a mouse the cells of minced im-
mune tissue are destroyed, but the effectiveness of the protection that
accompanies them may persist for at least two weeks.

The importance of a chemical approach to questions raised by this project
has been repeatedly emphasized. The recent advances in organic chemistry
have disclosed such elaborate organizations of protein molecules as to ap-
proach the assumed complex "organization" of living matter. The chemist
can no longer hold aloof from phenomena depending upon "organized" matter.
A specific substance may be associated with living matter in the form of
independent molecules operating as units ; again, a special configuration may
have no special effectiveness until it becomes established as an organic part
of a normal molecule ; or again, still more intimately, a special function may
arise from the reorganization of molecular structures already present. Such
considerations bear on several problems: on the nature of the change from
normal to malignant; on the chemical differences between strains of mice
genetically susceptible or resistant to certain transplanted leukemic cells;
on the materials responsible for induced resistance, whether occurring natu-
rally or put there by the host in combating growth of leukemic cells.

A significant broadening of the scope of the project has been made pos-
sible by the addition to this group of Dr. M. Bovarnick, working in the
Department of Bio-chemistry under Dr. Hans Clark at the College of
Physicians and Surgeons. During the year, Dr. Bovarnick has been ap-
proaching the problem of the mechanism of the resistance to transplanted
leukemia that is induced by normal tissue. Normal growth-controlling mate-

50 CARNEGIE INSTITUTION OF WASHINGTON

rials are eliminated because the effect is specific for a given genetic dif-
ferential between the constitution of the host and of the normal tissue used
in the treatment. If antigenic action is concerned, it is unprecedentedly
rapid (2 days) and calls for the startling assumption of antigenic similarity
between a substance that appears only in highly virulent leukemic cells
from one strain of mice and a substance found in all tissues of a certain
other strain without leukemia. That some new protective principle should
be involved seems entirely possible.

With the three biological variables — susceptible host, leukemic cells, and
protecting normal tissue — controlled to the point of giving virtually 100 per
cent results, a chemical analysis appears possible. The first step, however,
has proved very difficult. Conventional chemical analysis requires sepa-
ration from the vital organization of the cell; but all familiar procedures
known to eliminate living cells have rendered the residues of the normal
tissue ineffective. The pressure technique reported above has not been tested
on normal tissue.

Previously the normal tissue used was embryonic, and this type of pro-
tection has been designated embryo treatment, but this year, adult tissues
of the same strain have been found to be equally effective and, being far
more available, have been used regularly. By using the same organ (liver)
as for the passive transfer of immunity induced by leukemic cells, close
comparisons can be made between liver tissue that protects by virtue of its
genetic constitution, and liver tissue that protects by virtue of a non-genetic
change induced by leukemic cells. In spite of clear differences in the resis-
tance developed by these two different livers, the existence of the essential
substance in each case is closely bound up with living cells. Another sub-
stance is also intimately bound up with living cells — that responsible for
the malignant behavior of leukemic cells. To determine the relationship to
living cells in any one of these three cases would serve as an important lead
in the study of the others.

Specificity of Inducing Stimulus

Since the interpretation of phenomena occurring before our eyes has been
a leading policy, interest has been focused on the mechanism by which the
leukemic process, once initiated, is maintained, and upon the extrinsic fac-
tors that are in fact active in the production of leukemia in our colony,
rather than upon a search for chemicals that might experimentally induce
this malignant growth. However, the study of the genetic factors involved
in the observed incidence of spontaneous leukemia would be greatly aided
by a chemical treatment that would reveal genetic potentialities at an early
age. With this purpose, a study of the effect of a highly potent carcinogenic
agent, benzpyrene, was undertaken in cooperation with Drs. C. J. Lynch
and A. Claude of the Rockefeller Institute for Medical Research. In a
strain of mice inheriting a high susceptibility to leukemia would this chemical
hasten the appearance of leukemia? The evidence gives no indication of
any such hastening in the appearance of leukemia, but benzpyrene does
stimulate the occurrence of sarcoma as it does in other strains of mice.
While other investigators have reported leukemia as the main result of

DIVISION OF ANIMAL BIOLOGY 51

another chemical treatment, methylcholanthrene, the strain of animals em-
ployed did not otherwise show leukemia. The genetic constitution does
not merely render certain tissue liable to become malignant, but determines
susceptibility of certain tissues to certain agents. A genetic constitution
that renders primitive reticular cells susceptible to certain stimuli occur-
ring in our colony leads to leukemia; these cells are not susceptible to the
action of benzpyrene; another genetic constitution might make these cells
susceptible to the carcinogenic action of benzpyrene, and not to the stimuli
responsible for the spontaneous leukemia in our strain C58.

The developmental hypothesis of malignancy reported last year by Dr.
Potter has continued productively to guide thought and has been applied
to a new series of phenomena. According to this hypothesis malignancy
modifies the rate of normal cellular differentiation. This stands in contrast
to the view that malignancy depends upon the creation of a new, uncon-
trollable cell type that reproduces only itself.

Variation in malignancy, according to the new interpretation, changes
the rate of cell differentiation so that one or another stage preponderates,
but, according to observation, all stages are present and each stage apparently
divides at its own normal and characteristic rate. This includes advanced
stages no longer able to divide, which accordingly can no longer contribute
to progressive growth and so are no longer malignant. The continuation
of a leukemic population depends on the presence of incompletely differ-
entiated cells.

Lymphoid vs. Myeloid Leukemia

This hypothesis may now be broadened to cover the direction as well as
the rate of development. Under the usual conditions of transfer from mouse
to mouse the malignant factor in a given line has led differentiation con-
sistently in the lymphoid direction for many years and through hundreds
of normal hosts. But in hosts made incompletely resistant by normal tissue
treatment, the direction of development may change and populations appear
of leukemic cells in early stages of the myeloid series which terminates in
polymorphonuclear leukocytes. Such myeloid populations when transplanted
into untreated hosts may immediately develop into lymphoid leukemia with
all the specific characteristics shown before. The hypothesis does not imply
that early myeloid types have changed their course of development and
become lymphoid, but that malignant control has been temporarily modified
and, on return to a normal host, again directs the undifferentiated dividing
cells in the lymphoid direction, while the myeloid cells are soon left behind
by the new growth. In other cases more lasting change in the malignant
control is shown by the continued production of myeloid cells in the follow-
ing transfer or transfers. The outstanding instance of lasting modification
showed a gradual return to lymphoid leukemia in the course of numerous
transfers. In the tissue lesions of the hosts myeloid leukemic cells were
found in the first four transfers and not thereafter; in the peripheral blood
they persisted for thirty-four transfers.

Quite apart from the hypothesis regarding malignancy, the facts bring
myeloid and lymphoid leukemia very close together ; an unbroken continuum

52 CARNEGIE INSTITUTION OF WASHINGTON

of malignancy yields first one then the other type with return, abruptly or
gradually, to the first type. This gives direct support to the theory of a
common ancestral cell in normal animals, able to differentiate in either
direction according to the needs of the individual.

In man, lymphatic, myeloid, and "mixed" types of leukemia are known,
and even within the same case history changes in type have been recorded.
But the genetic relationship between the various types has remained unsolved
by clinical evidence. If the continuum responsible for malignancy controls
both the rate of development and its direction, this continuum is subject
to modification by the conditions of its environment. This environment in
turn is subject to experimental and clinical control.

Malignant Lymphocytes in Tissue Culture

Through the cooperation of W. H. and M. R. Lewis and the Department
of Embryology, living leukemic cells in tissue culture have been studied.
Cultures were made of three lines of transplantable leukemia and observa-
tions were made microscopically and with the aid of a motion picture camera.
At the conclusion of the observations on the living cells the cultures were
fixed and stained for further study and reference.

These studies on living cells confirm the conclusion, derived from earlier
studies with preserved material, that the malignant lymphocyte has the
same morphological characteristics as a normal lymphocyte of the same
stage of differentiation, and add the further observation that, according to
the Lewis criteria, the method of locomotion of the leukemic lymphocytes
studied is the same as that of normal cells.

Differences in transmission lines were evident during the early periods
of the cultures ; the most virulent line showed the largest number of blastic
cells moving out from the explant. The high mortality of lymphocytes after
the first day made further observations of little value. Roller tube cultures
kept for 7 and 9 days had very few demonstrable lymphocytes although
polymorphonuclear leukocytes were plentiful among the active fibroblastic
growth. The malignant nature of leukemic lymphocytes makes their culture
in artifical media no less difficult than that of normal lymphatic cells.

ENDOCRINE STUDIES

0. Riddle, R. W. Bates, J. P. Schooley, E. L. Lahr, G. C. Smith,
R. A. Miller, and L. H. Elwell

The regulatory powers of the anterior pituitary gland are now actively
studied in many laboratories throughout the world, and in this field of study
viewpoints may change markedly within a year. It has become clear that
the pituitary gland largely provides for the regulation, adjustment, and
coordination of the endocrine system, and for certain other activities of body
and mind besides. Fitting this generalization into the broader and basic
problem of organismal control and regulation, it would now seem possible
to conclude that in higher animals and man the brain and the pituitary
gland are the two prime sources from which the abilities of an individual are
derived.

DIVISION OF ANIMAL BIOLOGY 53

The investigations reported here, like those of past years, present parts
of an effort to learn those endocrine agencies and mechanisms which condi-
tion or control functions such as growth (development), reproduction, and
regulation in the bodies of higher animals and man. Much of the experience
of the year points to the unpredictability of relationships among hormones ;
and perhaps the most notable thing observed is the extent to which one
hormone may either increase (synergize) or decrease the specific action
of another. These studies of Dr. Riddle and his associates have been
greatly aided by a grant from the Carnegie Corporation of New York to
the Carnegie Institution of Washington.

The Preparation and Assay of Pituitary Hormones

We have now confirmed the report of others that the pituitary product,
or products (adrenotropin), which increases adrenal size in rats is not
prolactin. Our own preparations of adrenotropin, though containing only
insignificant amounts of other hormones, are apparently crude fractions.
During the past year all pituitary fractions obtained in connection with
our preparation of pituitary hormones have been assayed not only on
young pigeons but also on young rats. As a result of these routine assays
on rats Bates and Riddle have obtained further evidence that most of
our prolactin preparations are essentially free from adrenotropin, follicle-
stimulating (FSH), and luteinizing (LH) hormones.

Of notable value to the general task of purifying anterior pituitary
hormones is the demonstration of the usefulness of copper hydroxide for
freeing one or more pituitary hormones from troublesome amounts of
prolactin. After demonstration that Cu(OH) 2 precipitates prolactin quanti-
tatively from aqueous media at pH 6-7, this procedure was used to remove
residual prolactin from two FSH fractions, one of which was derived from
cattle pituitaries and the other from pig pituitaries. In neither of the
resulting final preparations was there enough prolactin present in 1.0 mg.
of product to provide a response with the local crop-sac test, showing that
there remained in these FSH preparations less than 1 part of prolactin to
10,000 parts of the purified substance. Early results further indicate that
a separation of thyrotropin from FSH may be accomplished by this same
method.

Last year Dr. White of Yale University reported the preparation of
prolactin in crystalline form, the first of the anterior pituitary hormones
to be obtained in this state. Twenty milligrams of this crystalline prolactin,
kindly supplied by Dr. White for our examination, was found to contain
about 6.5 Riddle-Bates units per milligram. Some of our own more recent
(noncrystalline) prolactin preparations have been found to contain as much
as 10 such units per milligram.

Much work involved in the technique of assays has been performed by
Mr. E. L. Lahr and Mr. L. H. Elwell. Mr. Graham Erdwurm has assisted
in general laboratory work and has shared especially in the numerous assays
made on rats.

54 carnegie institution of washington

Factors Affecting the Response to Prolactin

Since experience is proving that the quantitative response of the crop-
sacs of doves and pigeons is modified by a number of factors (see earlier
reports), it is necessary to identify and measure all such factors. Folley and
White recently reported that antecedent and simultaneous high dosage with
the ovarian hormone, dihydroestrone, markedly reduces the extent to which
prolactin normally increases the crop-sac weight. This finding has been
confirmed by Riddle and Bates, who obtain this diminished response
with purified prolactin, and also with prolactin admixed with all other
anterior pituitary hormones ; but in the latter case the decrease is markedly
less than in the former. Still other items of information concerning this re-
strictive factor were obtained which do not lend themselves to brief descrip-
tion here.

Folley and White also pointed out that their data, obtained with sub-
cutaneous injection of ovarian hormone and prolactin, show the existence
of a distinct sex difference (quantitative) of crop-sac response. Using
intramuscular injections almost exclusively we had never observed a signifi-
cant sex difference. Repeating the Folley and White experiments, and
using the subcutaneous route of injection, the sex difference they describe
has also been fully confirmed. In six different series (10 or more pigeons
each) we found the male crop-sac weights indicated 1.5 to 4 times larger
dosage than that indicated by the crop-sac weights of females.

Relations of Pituitary to Size of Body and Viscera

Observations reported last year concerning the effects of pituitary re-
moval, and of the ability of various pituitary fractions (hormones) to
sustain or promote general and localized growth, have been both confirmed
and extended. Very little will be noted here concerning this line of study,
which has been continued by Drs. Schooley, Riddle, and Bates.

When an unfractionated extract of the anterior pituitary gland is subjected
to the action of trypsin it has been found to lose apparently all its power to
repair the various disabilities that follow pituitary removal. This result
indicates that all the pituitary hormones which participate in maintaining
the weights of the body and particular organs studied are of protein nature.
Further observations of growth phenomena in organs and in the body as a
whole put emphasis on the high efficiency of a mixture of hormones. In
pituitaryless pigeons the growth of the body as a whole, and growth in at
least several of its parts (intestine, liver, pancreas, crop-glands, adrenal,
and gonads) , is accelerated more by mixtures of hormones of the pituitary
than by its purified hormones acting singly.

Hormonal Basis of Maternal Behavior and Broodiness

Three years ago, and on the basis of 160 tests, we reported that virgin
and adolescent male rats can be made "maternal" in behavior by injections
of prolactin, and that other pituitary hormones probably fail to induce this
response. A total of 1780 tests have now been made, and the later develop-
ments of this study conducted by Riddle and Lahr will be briefly sum-

DIVISION OF ANIMAL BIOLOGY

marized here. The accompanying table lists the hormones or substances
found to act positively in inducing maternal behavior in rats of four
classes — females, castrate females, males, castrate males. Another list of
hormones has been found either to have no similar action or actually to
inhibit maternal behavior; of these latter only a word need be said.

"Maternal" behavior induced in young rats by hormones
(The values given represent percentage of rats responding positively)

Sex

Control
reactors

Prolactin

Pro-
gesterone

Testo-
sterone

Inter-
medin

Whole
A. P.

Phenol

Females

Spayed females. . . .

Males

Castrated males ....

(28)
(32)

(23)
(28)

77
79

56
75

64
61

60
83

15
53

50
25

20
43

59
56

24
57

It will be noted that intermedin, presumably produced in the intermediate
lobe of the pituitary, induces this behavior; and extracts of the whole
anterior pituitary (A. P.), containing prolactin and other hormones, are
partially effective. One hormone secreted by the ovary (progesterone) and
another by the testis (testosterone) are markedly effective, though ap-
parently in lesser degree than is prolactin, while even carbolic acid seems
effective in some cases. Though an adequate explanation of these results
is not at hand there is some reason to suspect that progesterone and testo-
sterone, as administered here, cause a diminished production of estrin, and
perhaps also an increased release of prolactin from the rat's own pituitary.
Conceivably this may apply also to intermedin and phenol, although
evidence of depression of gonads by intermedin has been looked for and
not found. It is fairly certain that depression of germ gland activity is
one condition that favors the onset and exhibition of this parental behavior.
Injections of highly potent gonadotropic hormone have repeatedly stopped,
or diminished, maternal behavior after its natural occurrence ("reactors"),
and also after its induction by prolactin or other hormone. Tests made
with adrenotropin, cortin, parathormone, and thyroxine indicate that these
hormones have little or no action on the maternal behavior of rats.

The colchicine technique has been used to determine whether the initiation
of broody behavior in pigeons is or is not accompanied by a special or
unusual release of prolactin from the bird's own pituitary, and thus
whether an increased output of prolactin so coincides with the onset of
broody behavior as to permit it to be causally related to it. The results
show that this coincidence exists. At one day after the beginning of
broodiness the preceding normal rate of mitosis in the crop epithelium has
already increased by 600 per cent, and this higher rate is maintained and
still further increased during the incubation cycle, near the end of which the
secretion of crop milk begins. This result, involving a wholly new type of
evidence, therefore definitely supports the conclusion that prolactin plays

56 CARNEGIE INSTITUTION OF WASHINGTON

a significant part in the cyclic development of broody and maternal be-
havior in higher animals.

Still other tests made by Riddle and Schooley relate importantly to this
question of the mechanism through which the "broody instinct" arises in
birds. They find that the corpus luteum hormone, progesterone, is capable
of playing a part directly or indirectly in the initiation of broodiness in
ring doves. Utilizing the "pellet implantation" method introduced by
Parkes and Deansley, suitable tests were carried out — tests which avoid
disturbances incident to repeated handling and injection of the birds.
Implantation of such pellets of crystalline progesterone into adult and
sub-adult ring doves, mated or unmated and of both sexes, is followed
within 2 to 4 days by definite broody behavior. A pair of males thus
treated carried out the incubation of eggs and the feeding of young. This
ability to feed — the production of crop milk — demonstrates a release of extra
or unusual amounts of prolactin prior to the end of incubation ; but it has
not yet been proved that in these particular cases (see above for pigeons)
this release also occurs at or before the beginning of broodiness. Continuous
dosage with progesterone was shown to be unnecessary, since birds completed
the brooding cycle after the pellets were removed. It is also notable that
immature doves do not react in this manner to this same treatment.

Cytology of the Pituitary and Adrenal

An understanding of the structural basis of hormone production by
anterior pituitary cells requires a correct interpretation of the life cycle
of these cells, and no interpretation is susceptible of proof by direct observa-
tion. Nevertheless the subject is being studied with some success through
indirect approach by Drs. Schooley and Riddle. Experimental modification
of pituitary structure by treatment with hormonal and pharmacological
agents, and by surgical procedures, have given some instances of nearly
pure cultures of particular types of pituitary cells which can be correlated
with known indices of physiological activity in the body of the animal.

In the pigeon's pituitary the undifferentiated cell (chromophobe) is
interpreted as an embryonic element capable of maturing into either
acidophil or basophil. These latter cells produce and release the hormones
characteristic of the anterior pituitary and then die or undergo dedifferentia-
tion into chromophobes. Indications were obtained of the manner in which
the differentiated functional cells accomplish this dedifferentiation. The
granulations seen in the pituitary cells seem not to be the active or actual
hormone; and therefore the release of hormones does not rid the cell of the
accumulation of granules present during active secretion. Apparently,
however, such cells throw out this accumulation of granular material and
are thus rejuvenated for a new cycle of activity. This discarded material
accumulates between and outside the cells and becomes the pituitary "col-
loid" observed in the pituitaries of most animals. The rejuvenated cells have
embryonic characteristics and appear to undergo further division, thereby
producing a new supply of chromophobes which take up the work of hormone
production as they mature into chromophils.

DIVISION OF ANIMAL BIOLOGY 57

The adrenal cortex produces one or more hormones under the stimulus
of one or more pituitary hormones. The cytological changes that occur
in the adrenal glands following hypophysectomy, and following administra-
tion of various pituitary hormones to normal or hypophysectomized pigeons,
have been studied during the past year. A rich supply of adrenal tissue
from birds previously subjected to many types of treatment is obtained
in connection with other current investigations, and Dr. Richard A. Miller
has studied the cytological changes thus induced in the cortical cells.
It has been found that in the normal bird these cells contain very little
fat; that hypophysectomy is followed not only by the well-known decrease
of cortical tissue but by a great accumulation of fat (up to more than half
of the cell volumes) in the persisting cells; that this accumulation of fat
is progressive during more than 10 days (probably during 20 or 30 days) ;
that such accumulation of fat is prevented by administration of whole
extracts of anterior pituitary and by pituitary fractions rich in adrenotropin ;
and that these two types of pituitary preparations, even in fasting hypo-
physectomized birds, tend to increase the mitochondria and to restore the
Golgi apparatus to or toward the condition found in the normal unoperated
bird.

Pituitary Hormones and Carbohydrate Metabolism

Both uncertainty and confusion characterize current reports concerning
the pituitary hormones which affect carbohydrate metabolism. Further
studies on one aspect of this problem have been made by Dr. Riddle, in
association with Dr. Louis B. Dotti of New York Medical College. Prolactin
moderately but consistently increases the blood sugar in all types of
pigeons, in doves, and in rabbits (New Zealand Whites). In these species
prolactin acts upon the blood sugar in much the same way (though in
somewhat less degree) as do extracts containing all the pituitary hormones.
Adrenotropin also is found to have a somewhat similar action on blood
sugar, and still other results provide evidence that at least two different
pituitary products affect the metabolism of carbohydrates.

Following Collip's recent report on the glycemic action of intermedin in
rats and dogs, a new interest attaches to the action of that hormone. A
slight glycemic action of intermedin was observed in normal rabbits and
pigeons, but even a slight action was absent in eight tests made on hypophy-
sectomized pigeons treated for 5 to 8 days. Details connected with these
studies indicate that it is not possible to ascribe to intermedin the effects
on blood sugar and basal heat production of pigeons which we have assigned
to prolactin. The prolactin crystals of White, even in the low dosage
used, increased the blood sugar of hypophysectomized pigeons.

Basal Metabolism in Functional Regulation

It becomes increasingly important to know which pituitary hormones
have an action on basal heat production. More than a year ago O'Donovan
and Collip reported that the hormone usually known as intermedin also
has power to raise the B. M. R. in rats. That result made it necessary
to learn whether intermedin and prolactin have comparable effects on the

58 CARNEGIE INSTITUTION OF WASHINGTON

B. M. R. of pigeons. This and some related problems have been studied
by Riddle and Smith during the present year.

Intermedin, prepared and assayed in Hochst, Germany, and obtained
through the courtesy of the Winthrop Chemical Company, was injected
daily (500-1000 Phoxinus units) for 3 to 10 days into groups of pigeons.
Measurements (36) made on normal pigeons 6 hours after a last injection
of the hormone gave slightly higher (4 to 7 per cent) values for the heat
production; other measurements (10) on hypophysectomized pigeons gave
values 2 per cent above their control. The insignificant differences observed
seem to demonstrate that intermedin and prolactin do not have comparable
effects on the B. M. R. of pigeons.

The action of small amounts of the crystalline prolactin of Dr. White
was studied in small groups of hypophysectomized (4) and of normal (8)
pigeons. The former group was studied after 3 daily injections of 3.3
units (0.5 mg.) and the B. M. R. was found to be increased by about 14
per cent; the normal pigeons received one-half the above noted dosage
during 3 days and at that time showed basal values increased by 12 per cent.

The action of adrenotropin on heat production is being studied. Two
groups of normal pigeons given heavy daily dosage (10 mg.) during 3 and
9 days, respectively, increased their heat production values by 9 per cent.
Since 10 mg. of this preparation of adrenotropin contains nearly 1 unit of
prolactin, and since we cannot now declare it to be entirely free from
thyrotropin, these incomplete data indicate that adrenotropin has little
or no effect upon the basal heat production of pigeons.

Useful but now little-understood results were obtained from a comparison
of the basal metabolism of normal and hypophysectomized young (2-month)
pigeons, when both types were continuously fasted during 10 days. Measure-
ments made on small groups of these two types of pigeons gave the un-
expected result that at 5, 7, and 9 days after removal of their pituitary
glands, and at 6, 8, and 10 days of fasting, these pigeons have a higher
metabolic rate (measured at 30° C.) than have unoperated birds similarly
fasted. At the above-named periods the operated group produced only
9, 8, and 5 per cent less heat than when unoperated (and fasted for only
24 hours) ; but the unoperated group at these periods of advanced fasting,
produced 19, 27, and 31 per cent less heat than when fasted for the standard
period of 24 hours. Our study of heat production in these and other
related conditions continues to assist an interpretation of the mechanism
of pituitary action.

Other Studies and Activities

Last year Dr. Bates reported a rapid method for the determination of
the tryptophane content of proteins. Further studies have shown that the
intensity of color developed by that method can be increased about 10
per cent and the small but disturbing drift of intensity previously present
can be eliminated. These desirable results were obtained by using a
smaller amount of HC1 (30 ml./lOO ml. final volume), and by diluting
to volume with 50 per cent ethanol instead of with water. With these
improvements the method gives excellent and reproducible results.

DIVISION OF ANIMAL BIOLOGY 59

Utilizing the recently introduced technique of McGinty and associates for
demonstrating qualitatively the presence of extremely minute amounts of
progesterone, Riddle and Schooley have tried to learn whether the corpus
luteum hormone, progesterone, is produced in birds. Two types of bird
ovaries were taken as possible sources and extracted according to the method
of W. M. Allen (1932) ; in each case approximately 15 g. of fowl ovaries
(yolk previously removed from follicles) were extracted. One sample of
ovarian tissue was obtained from actively laying hens; the other sample,
of similar fresh tissue, was from hens in various phases of egg production
but previously injected (with prolan) daily for three days in an attempt to
luteinize their ovaries. Neither of the resulting purified extracts contained
enough (1 gamma) progesterone to produce a positive reaction in the
prepared uterus of a suitable rabbit. The best available evidence on this
point therefore indicates either that such fowl ovaries do not produce
progesterone or that they produce an amount nearly or quite insignificant
in comparison with that formed in the ovaries of adult mammals.

Studies initiated but not reported last year showed that a rapid
hyperplasia of the crop-sac epithelium of pigeons quickly follows the
injection of prolactin, and that this can be clearly and quantitatively
measured by the colchicine technique. Details concerning quantities of
colchicine (0.6 mg. per 500-g. bird) and time of injections of both the
drug and the effective prolactin have been learned and published by Lahr
and Riddle. This method was further used in the study of several related
problems. In the crop-sacs of adult pigeons it was found that an injection
of prolactin (60 units) is followed by (induced) cell divisions within less
than 30 minutes; the maximum rate of mitosis occurs after 2 hours, and
the effect is not observable after 10 to 12 hours. When a second injection of
prolactin is given 8 hours after a first, this has produced a greatly
enhanced effect 2 to 4 hours later. Mr. L. H. Elwell has assisted in the
determination of the extent of this increase in mitotic rate following the
administration of prolactin.

In a study made during a few months of summer, Riddle and Dotti have
confirmed and extended their work reported last year on the calcium-
raising properties of female sex hormones. Sufficiently high dosage has
now been shown to be effective in castrate male rabbits; but very high
daily dosage (3 mg.) of estrone to rats may be less effective than much
lower dosage, and under no dosage hitherto used is the blood calcium of
rats greatly increased. Recent results show that estrone is wholly incapable
of increasing the serum calcium of parathyroidectomized rats. This result
favors the view that the action of the sex hormones on the serum calcium
is secondary to their action on the parathyroids.

Several theoretical considerations make it worth while to know which
of the many compounds chemically related to the group of sex hormones
is capable of causing growth in the uterus. And from a phylogenetic
standpoint this same information has added interest when it pertains to
the uterus (oviduct) of a bird. A current study of this problem is being
made by Riddle and Lahr, to whom Dr. Erwin Schwenk of the Schering
Corporation has supplied generous quantities of the crystalline compounds.

60 CARNEGIE INSTITUTION OF WASHINGTON

The quantitative effect of these substances evidently undergoes unexpected
seasonal variations, and this fact precludes a satisfactory description of
these results at this time. Dihydroestrone, estrone, progesterone, andro-
stendiol, dehydroandrosterone, testosterone, androsterone, and pregneno-
lone have all proved effective (and in nearly this order) on the oviducts
of ring doves injected daily (1.5 mg. or less) for 7 days; cholestenone was
ineffective. The effect of estrone on the dove oviduct is markedly synergized
by progesterone. Possible and interesting theoretical implications of this
particular fact may be noted. Though progesterone seems not to be pro-
duced in birds (see above), their oviducts, like the uteri of mammals, are
capable of reacting markedly to the presence of this hormone. This suggests
that when evolving mammals produced progesterone for the very first time
the chief tissue (oviduct, uterus) upon which the hormone acts was already
sensitive to its presence. Thus it is unnecessary to postulate a coincident or
concurrent origin of two genetically unrelated things — a new hormone and
a new or special sensitivity of a particular tissue to that hormone.

STUDIES IN EUGENICS AND HEREDITY

Harry H. Laughlin

Survey of the Human Resources of Connecticut

Early in the year which ended June 30, 1938, the task allotted in the col-
lection of data, both by first hand field work and by correspondence, was
completed, and during the latter half of the year the main efforts of the
Survey were expended in the analysis of the returns and in the preparation
of the Survey's Report No. 1.

The following progress report reviews briefly several researches conducted
by the Survey:

Analysis of the Laws op Connecticut in Direct Reference to the Human Resources

of the State

(a) The constitutional law of Connecticut which defines and limits the
function and authority of this sovereign state in its control of population by
numbers, race, and inborn quality. This analysis of the legal background
of the eugenical function and authority of the state covers the basic items of
(1) definition, (2) population, (3) quality, (4) race, color, alienage, (5)
migration control, and (6) the census and control of handicapped persons,
in the main historical and legal documents which laid the governmental
foundation of the present Commonwealth.

(b) Statute-reference and abstract of the laws of Connecticut which bear
directly upon the eugenics of the Commonwealth, i.e., upon the establishment
and maintenance of racial ideals and family-stock standards, upon the deter-
mination and maintenance of the optimum total population number and dis-
tribution, and specifically upon handling the inadequate and handicapped
members of the population. This analysis covers the General Statutes of
Connecticut in force on January 1, 1938; that is, the General Statutes of Con-
necticut, Revision of 1930, and the Session Acts of 1931, 1933, 1935, and 1937.

DIVISION OF ANIMAL BIOLOGY 61

The present analysis of the statutes of Connecticut presents a new point of
view in the study of state law. Its purposes are, first, to enable the student
of human resources to locate immediately the statute reference with a short
abstract of every law which bears upon any one of the several eugenical sub-
jects listed. The second purpose is to bring together with special clarity, and
organized in systematic manner, all laws of the state which bear upon the
subject of eugenics or race improvement, and thereby to enable judgment of
the completeness, orderliness, and adequacy of the statutes on this subject,
with special facility in locating any gaps, contradictions, overemphasis, or
repetitions which may exist therein. The third purpose is to indicate a
possible codification of the laws of the state in reference to the conservation
of its human resources.

The 169 Towns of Connecticut, Each in Relation to Its Problem of Inadequate and

Handicapped Residents

The state of Connecticut is divided into eight counties. These eight coun-
ties, in turn, are composed of 169 towns in all. In Connecticut the county
government is of little consequence compared with that of the state on the
one hand and the town on the other. The real center of local government
in Connecticut is the town.

The Survey of Human Resources assembled the basic geographic and demo-
graphic statistics of the 169 towns, and added to them the findings of its own
first hand researches on the inadequate and handicapped residents of each
town. These studies covered the census of inadequate and handicapped indi-
viduals resident of the town, the town's responsibility for such residents and
how the town discharges such responsibility, and the classes and numbers of
such residents who are cared for by the state custodial or residential institu-
tions for the inadequate or handicapped classes.

The Problem of the Feeble-minded in Connecticut

This Survey has given a special consideration to the problem of the feeble-
minded within the population of the state. Making critical use of the most
accurate standards for the mental measurement and the diagnostic classifica-
tion of the feeble-minded, the present Survey collected and analyzed the case
histories of the 11,962 definitely feeble-minded residents of Connecticut. It
is estimated that, using the same standards, a complete census of the mentally
deficient in the state would have found the total number of such defectives
equal to approximately 17,500, or practically 1 per cent of the entire popula-
tion of the state.

These 11,962 feeble-minded persons — the total number who came under the
purview of the Survey — have been studied individually in reference to nine
subjects, as follows: (1) sex, (2) age, (3) recidivism, (4) diagnostic class,
(5) intelligence quotient, (6) race descent, (7) nativity, (8) citizenship,
(9) kin in institutions.

The present Survey has completed twenty-one tables of cross-classification
by pairs of the above listed traits and qualities for selected group units and
totals within this population.

CARNEGIE INSTITUTION OF WASHINGTON

Cross-Classifications of Traits and Qualities of the Inmates of Institutions and
Other Selected Socially Inadequate or Handicapped Population Groups of Connecticut

In this section of the Survey of the Human Resources of Connecticut, 19
portfolios consisting of a total of 346 cross-classification tables have been
worked out.

The purpose of this system of classification is to provide more definite facts
in reference to the history, characteristics, qualities, and origins of the par-
ticular social class or population group which is under analysis. In the cur-
rent researches particular attention has been paid to the cross-classification
of such matters as, for example, race descent against intelligence quotient;

Tirst Subject: INTELLIGENCE QUOTIENT and Class Limits or Types

-J
U

26-50

51-70

71-80

81-CjO

91-110

111-125

Unknown

TOTAL

CRIMES AGAINST
CHASTITY

.250
.231

27
.227

.214

23
.193
.177

.210
.170

12
.101
.154

29
244
.175

1.000

.180

CRIMES AGAINST
PERSONS

3
.012
.231

36
.135
.286

43
.165
331

60
.231
408

27
.104
346

91
350
.548

260

1.000

•393

CRIMES AGAINST
PROPERTY

7
.028
538

56
.225
444

537
454

55
.221
374

35
.140
.449

.004
I.00C

36
.145
.217

249

1.000

.377

CRIMES AGAINST
PUBLIC POLICY

7
.212
.056

.152
.038

7
.212
.048

4
.121
.05!

10
303

.060

I.OOO
.090

TOTAL

13
.020

I.OOO

126

.191

1.000

130

197

1.000

147
.222
1.000

78
.118
1.000

JD0I

1.000

166
551

1.000

661

1.000

Fig. 1. Sample cross-classification, intelligence quotient against diagnostic class,
for the 661 inmates of the Connecticut State Prison for Men at Wethersfield,
September 1, 1937

race descent against diagnostic class; or kin in institutions against intelligence
quotient.

A representative study of the social inadequates of the state. Besides the
inmates of several other institutions, the inmates of the Connecticut State
Prison for Men at Wethersfield were cross-classified by pairs of subjects
among the above listed nine items. Selections from these cross-classifications
give many direct questions and answers such as the following:

What is the comparative intelligence-distribution among those Connecticut men prisoners of
Italian descent and those of American blood, for whom I. Q.'s have been computed?
Answer :

I.Q.

Prisoners of Italian descent
(per cent)

Prisoners of American blood
(per cent)

26-50

2.39
32.59
29.02
25.60
10.40

1.91

51-70

20.79

71-80

81-90

26.36
28.36

Above 90

22.68

Total

100.00

DIVISION OF ANIMAL BIOLOGY

What is the distribution of intelligence among the 119 men committed to the Connecticut
prison for crimes against chastity — the so-called sex crimes?
Answer :

Percentage of prisoners
I. Q. committed for sex crimes

26-50 2.5

51-70 22.7

71-80 19.3

81-90 21.0

Above 90 10.1

Unknown 24 . 4

Total 100.0

It is noted that the idiot class, I. Q. 0-25, is not represented among these
prison inmates, and that for nearly one-fourth (24.4 per cent) the I. Q. is
unknown.

The Direct Cost to the People of Connecticut through Expenditures by the State
Government (Exclusive of Expenditures by County and Town Governments and by
Private Philanthropy and Charity) for the Maintenance, Care, Training, and
Treatment of the Defective, the Dependent, the Delinquent, and the Handicapped

Classes

The Survey made a special analysis of the relative and absolute costs of
the inadequate and handicapped population to the state government of Con-
necticut for the fiscal year 1935-1936 as compared with the fiscal year twenty
years previous, 1915-1916.

While the money cost has mounted, the economic drag and the biological
cost, as other items of the Survey have shown, have mounted still more
rapidly, and the state is thus confronted with serious financial, economic,
and biological problems, in the increasing numbers of inadequate and handi-
capped members of its population by reproduction and net migration, as com-
pared with the competent and adequate members of the state's population
and their relatively lower reproductive rates and net migration gains.

Change in twenty years (1915-1916 to 1985-1936), or in but little more than one-half of one

human generation

Estimated population

State governmental expenditures for all purposes

Such per capita expenditures for all purposes . . .

Total expenditures for defective, dependent,
delinquent, and handicapped classes

Portion of total state expenditures devoted to
defective, dependent, delinquent, and handi-
capped classes

Per capita cost

1915-1916

1,219,174

,339,428.00

$6.02

,503,022.00

20.5%

$1.23

1935-1936

1,734,000

$47,436,626.94

$27.36

$11,479,544.66

24.2%
$6.62

Per cent
change

+ 42.23
+546.33

+354.48

+663 . 76

+ 18.04
+438.21

From these data such conclusions as the following may be drawn: (1) In
1937 the people of Connecticut were expending, through their state gov-
ernment (exclusive of county, town, municipal, and private expenditures),

64 CARNEGIE INSTITUTION OF WASHINGTON

more per capita for the maintenance, care, training, and treatment of their
socially inadequate and individually handicapped classes than this state gov-
ernment was expending for all purposes twenty years ago. (2) At the present
rate every inhabitant of Connecticut is expending, through his state govern-
ment, five and one-third times as many dollars per year on the socially
inadequate and the individually handicapped as the average inhabitant was
spending for the same purpose twenty years ago.

Experimental Census and Registry

One unit study in the Connecticut Survey of Human Resources is called
"The Experimental Census and Population Registry of One Town." A
representative town of about 2500 inhabitants was made the subject of
this study, and field work was undertaken to make a census and registry
of as large a portion of its population as available field workers would
permit.

A card was designed and used as the basis of this experimental population
enumeration and registry. The specific additions included such matters as
personal identification by fingerprints, classification by race descent, and
relationships to near blood-kin and to relatives by marriage. This card,
which was used in the present experimental census registry, provides for
records which show more definitely than the usual census the status and
change of the subject-population in reference to race descent, tongue,
literacy, medical case history, reproductive rate, occupation, employment,
and economic condition, as well as family connections and conditions.

Studies in Human Heredity: Actuarial Genetics

During the year steady progress has been made on the analysis of stature
inheritance in the American population, and concurrently in the development
of the actuarial aspect of genetics. In the latter researches, the main ques-
tion is : "When a given problem in human heredity is presented, accompanied
by certain definite data concerning the possession or degree of development
of the subject-trait among certain definite near-kin, by what probability
will the pre-indicated offspring possess the named quality to the specified
degree?" The subject-trait in its somatic development may be almost
entirely hereditary; it may be almost entirely environmental; it may be
a resultant of these two developmental forces acting in a definite combination ;
and the hereditary part may be based upon one Mendelian gene or upon a
complex of many. In any case the actuarial probabilities are worked out by
comparison of Nature's behavior in the antecedent distribution of the subject-
trait within the subject-family as given with the same trait distribution
among definite blood-kin within other families drawn from the same general
population, all other factors being randomly represented.

Clinical Service in Human Heredity

Up to the present time the Eugenics Record Office has not served, nor in-
tended to serve, in the capacity of a clinic in human heredity, but in an in-
creasing degree such possible service is being forced upon the attention of the

DIVISION OF ANIMAL BIOLOGY 65

institution. Inquiries, either directly or by reference from other laboratories
which were addressed directly, are sent to the Eugenics Record Office by
intelligent members of families with specific problems in human heredity —
physical, mental, or spiritual. They are sent also by physicians and friends
of handicapped subjects, particularly by physicians who have not specialized
in human genetics and who, therefore, call upon research students who have
become expert in this field to collaborate with them.

In experimental response to these demands for clinical service in the field
of human heredity, a new survey of the present status of knowledge of the
rules of inheritance of given diagnosable and measurable human qualities
has been undertaken, with the possibility of practical clinical service con-
stantly in mind. The individual who applies to a clinic of this sort presents
a definite problem in human heredity and desires an answer in the form of a
definite "yes" or "no," or, at least, an answer in terms of dependable proba-
bilities— as dependable for instance as the actuarial probabilities computed by
a reliable insurance company in its own field.

Genetics of the Thoroughbred Horse
Racing Success of Laboratory-produced Thoroughbreds

For many years Walter J. Salmon of New York City, distinguished breeder
and racer of the Thoroughbred horse, maintained in conjunction with the
Carnegie Institution of Washington a laboratory for research on the measure
and inheritance of racing capacity. The scientific work of this laboratory
was conducted by the Eugenics Record Office at Cold Spring Harbor, Long
Island. A part of this work consisted in assembling and analyzing racing
records of individual horses and of groups of definitely related Thorough-
breds. The second part of the laboratory consisted in the breeding farm,
which put to experimental test the findings and indications of the researches
in the racing and pedigree analysis. This experimental breeding farm was
maintained by Mr. Salmon as the Mereworth Stud, in Lexington, Kentucky.

This laboratory in the course of its experimental breeding for the produc-
tion of high racing capacity produced two of the most successful racing
Thoroughbreds of recent years. These horses are:

Discovery, by Display, out of Ariadne; date foaled, 1931

Flat racing capacity, 140.93; number of races run, 63; number of races won, 27;
number of races in which the quality of performance was above 1.000, 16.

Battleship, by Man 0' War, out of * Quarantaine ; date foaled, 1927

Flat racing capacity as a 2-, 3-, and 4-year-old, 123.48; number of flat races run,

22; number of flat races won, 10.
Won Grand National Steeplechase at Aintree, England, March 25, 1938. Time,

9:29 4/5; distance, 4 miles, 856 yards; number of competitors, 13.

Research Publications

In January 1938, the complete texts for the so-called "Black Book," which
is the practical work-volume to accompany volume I on the Measure of
racing capacity, and for the so-called "Brown Book," which is the practical
work-volume to accompany volume II on the Inheritance of racing capacity,

66 CARNEGIE INSTITUTION OF WASHINGTON

were deposited with the Washington office for publication. These two books
contain the formulae and tables necessary for actual use (1) by the judge
of racing capacity in the individual horse, and (2) by the practical breeder
in planning mate selection for high racing capacity in the foal. The two
basic volumes with their respective work books will complete the series of
studies as originally planned on the genetics of the Thoroughbred horse.
Volumes I and II will give the original data and their analyses which devel-
oped respectively the yardstick for the measure of racing capacity and the
formula for predicting racing capacity in the foal. The experimental work
has been finished, and the texts and figures for volumes I and II are in course
of preparation for publication.

ANTHROPOLOGY AND HUMAN GENETICS

Morris Steggerda and Mary Elizabeth Grant

Growth in Children of Different Races

The work on the physical development of approximately 400 children
belonging to the Negro, white, Navajo, and Maya races has continued
throughout eight years. During that time, two height-weight-age tables
were prepared, one for Navajos, the other dealing with Dutch whites in
Michigan. With their publication, the need of intensive studies on homo-
geneous groups was stressed. Up to this time, our studies have concerned
chiefly cross-sectional data. In this report, we are able for the first time to
present some findings from our longitudinal material. The growth trends for
males and females of the four races previously mentioned, based on average
annual increments of stature, are shown in figure 1. These curves were made
following a system described by Shuttleworth.1 The mean stature at a
base age involving the greatest number of available cases was selected (age
eleven, in this study), the average annual increment between 11 and 12
years was added to this mean, and the 12- to 13-year increment added to
the 12-year figure, etc. The average increment between 10 and 11 years
was subtracted from the mean of 11 years, and that between 9 and 10 was
subtracted from the 10-year figure, etc. This method has the advantage of
greater reliability in indicating the pattern of growth than can be obtained
by cross-sectional data. For each age and sex the number of individual
increments ranged between 20 and 50.

From figure 1, it will be noticed that the Maya are approximately 10 cm.
shorter for each age than the Navajos, who in turn are consistently shorter
than the Dutch. The Negroes are taller than the Dutch for all ages up
to 14, when the Dutch surpass them and remain taller into adulthood.

It is generally known that white boys are taller than girls from the ages
of 6 to approximately 11, at which time the girls are taller than the boys
until approximately 14 years, when the boys again lead in stature. From
figure 1 it will be seen that this same general condition holds for all the
races, except that for the lower years the points of the first decussation
occur at different ages. Thus, for the Maya the point is at 9 years, for

1 F. K. Shuttleworth, Sexual maturation and physical growth of girls age six to nineteen.
Monographs Soc. for Research in Child Development, vol. 2, no. 5, pp. 217-219 (1937).

DIVISION OF ANIMAL BIOLOGY

Navajos at 10 years, and the Dutch seem to have two points, one at 7.5
years and the other at 11, while for Negroes the point of decussation occurs
at 9.5 years. It is of interest, however, to note that the second point of
decussation, or that age at which the males again become taller than the
females, is between 13 and 14 years for each race.

ai
O

—

•-
<r

180^

175

170

165

160

155

150

145

140

135

130

125

120

115

110

105

100

Male -
Female -

MAYA

Negro

Dutch

Navajo

Maya

8 9. to. II. 12. 13.
Age in Years

(4.

15.

18.

Fig. 1. Growth trends for males and females of four races based on average annual

increments of stature

The growth trends in stature for males of these different races is curiously
the same. The average annual increment decreases from 6.5 to 10.5 years
of age for each race, at which time the rate increases until 14.5 years, after
which the rate falls. This means that at 10.5 years there is a minimum of
growth for each race considered, and at 14.5 years there is a maximum of
growth for each of these races. After this age the rate of growth decreases
rapidly for all races with the Navajos decreasing at a slightly slower rate
than the others. This similarity of growth is of interest when one considers
that these groups live in entirely different habitats. The Navajos, for ex-
ample, live at an altitude of 6000 feet, while the Maya live practically at
sea level and in a subtropical region. The Dutch whites live in the northern
United States, while the Negroes live in Alabama. The food habits of these
different races are likewise very different; for example, in the main, the
Navajos are protein eaters living on mutton when they can, whereas the
diet of the Maya consists of from 75 to 80 per cent maize products. The
average annual increments for girls of these same races are not quite so
definite, although they follow practically the same general growth trend.
The Negro, Dutch, and Navajo girls reach their highest rate of growth
between 11 and 12 years, after which the rate of growth decreases; the Dutch,

CARNEGIE INSTITUTION OF WASHINGTON

however, continue to grow at the same rate for another year. The Maya
girls grow less at every age than do the other three races up to the age of
13 years, after which the Navajos and Negroes have lower increments.

The question was asked whether individuals who were short at an early
age attained the average stature of the population, or whether they remained
short throughout life. Twelve individual Maya boys were selected at
random, all of whom were taller than the mean 11 -year-old stature for the
race. Likewise, 12 individuals, all of whom were shorter than the 11-year-
old mean, were selected and their annual growth plotted. This same pro-
cedure was followed for 24 Maya girls. The curves for males show that
the two groups remain relatively separate; that is, the tall 11-year-old boys
were taller at every age for which we measured them, and the boys who
were shorter than the average at 11 years were shorter for every other age.
It will be noticed that the curves for the short boys begin to flatten out at
16 and 17 years, indicating that their growth is nearly completed. The
curves for girls are practically the same except that at the older ages, 14
and 15 years, the short girls continue to grow, whereas the taller girls have
stopped growing at those ages. These statements are preliminary and more
data are being gathered for more conclusive evidence.

MAYA

H 57

Navajo

Dutch

o 56

Negro

£ 55

- 54

H 52

e> 51

****ni

1- 50

£ 49

^w™.

*""* "Xl

/ .--'

^^ s

> 47

--,

•-

*»*

^ s

< 46

£T 45

10 II

12 13 14 15

16 17

Fig. 2.

Age in Years

Mean relative chest girth for male children of four races

Cross-sectional data show that the Maya children have relatively large
chests when compared with Navajos, whites, and Negroes (see figure 2).
Male children of each of these races have a lower relative chest girth at the
ages of ten to fourteen than they do at six or eighteen years of age. That is,
male children just previous to the adolescent spurt of growth for these four
races are relatively slender. The Maya children are least slender; for

DIVISION OF ANIMAL BIOLOGY 69

example, at thirteen years of age, the average chest girth for Maya boys is
51.4 per cent of their stature. For Navajo boys the ratio of these dimensions
is 48.3 per cent. Dutch whites, who are still more slender, have a chest
girth which is 47.3 per cent of their stature at thirteen years of age, while
Negroes, who are most slender, have a relative chest girth of 46.3 per cent
for this age. These differences are all statistically significant. The differ-
ence between the mean relative chest girth of the Maya and Navajo is
12 times the probable error of the difference. Between Navajo and Dutch,
the difference equals 4 times the probable error, and between Dutch and
Negroes, the difference is more than 3 times the probable error of the
difference.

Ethnobotany of the Maya Indians

In a study of the medicinal usages of 25 plants used by the Maya of the
Chichen Itza area, it was found that 11 of them have been used consistently
by colonial and modern doctors and the Indian herb doctors, as well as by the
lay Indians, for some specific ailment. It is of interest and perhaps of
significance to note that these 11 plants are used widely and have been used
specifically for nearly four hundred years. Thus, Euphorbia hirta L. and
Rauwolfia heterophylla R. & S. have been used over this period for sore
eyes and granulated lids, but their properties are so well known that even
the yerbateros (herb doctors) go to considerable detail in warning the public
not to use too much of these dangerous plant juices. For coughs and colds,
Mimosa hemiendyta Rose & Robins, has been used over this entire period
by educated doctors and uneducated Indians alike. Jatropha Gaumeri
Greenm. has been used consistently for mouth sores, as well as for diarrhea
and dysentery, which may indicate that the plant contains a drug which
acts on the mucous membranes of the mouth and intestines.

If the number of times a disease is mentioned by independent sources for
treatment indicates the prevalence of the disease, then diarrhea and dysen-
tery, coughs and colds, fevers and chills, skin diseases, sores and ulcers, and
kidney trouble and urinary disorders are most abundant, each having been
cited twenty times or more. Everyone acquainted with the tropics knows that
the above-mentioned diseases, with the possible exception of kidney trouble,
are exceedingly common, and the incidence of these disorders as given by
Shattuck 2 proves that this contention is true. Next in importance are
hemorrhage, sore eyes, and snake bites. Tuberculosis is mentioned only
once, unless blood vomit may be so considered. Confirming this, Shattuck
states, "We saw in our clinics very few cases of pulmonary disease which
were typical or even suggestive of tuberculosis." Malaria is mentioned only
twice, but may have been considered under a heading of aches and pains,
or another general group called fevers and chills, although the modern Maya
readily distinguish between malaria and other fevers. Syphilis and gonor-
rhea are mentioned only by the colonial and contemporary doctors and
never by yerbateros. This might bear out the findings of Shattuck, namely
that the modern Maya are comparatively free from both of these diseases.

2 G. C. Shattuck and collaborators, The Peninsula of Yucatan: Medical, biological,
meteorological and sociological studies. Carnegie Inst. Wash. Pub. No. 431 (1933).

70 CARNEGIE INSTITUTION OF WASHINGTON

He says (page 257), "Clinical evidence of syphilis was found to be prac-
tically nil, alike in the Maya and in the Mestizos of our series." It may be
that the colonial and contemporary doctors treated chiefly Spaniards for
these diseases.

Eye trouble, including conjunctivitis and granulated lids, is listed rather
often in the text material, and two plants (Euphorbia hirta L. and Rauwolfia
heterophylla R. & S.) are consistently used for its specific treatment. The
Maya are reputed to be relatively free from trachoma, although folliculosis
is common among children. Toothache, pyorrhea and gum trouble, sore
mouths, and fever sores seem to be relatively common. For toothache, one
plant has been used consistently, namely Krugiodendron ferreum (Vahl)
Urban. Snake bites have also been treated uniformly throughout the his-
toric period of Yucatan by Pisonia aculeata L.

The purpose of this small study was to determine whether the modern
usages of plants were the same as those in the seventeenth and eighteenth
centuries. It was learned that this was true for 44 per cent of the 25 plants.
During this time, from ten to fifteen generations have elapsed, and the in-
formation has been handed down chiefly by word of mouth. The modern
yerbateros are illiterate and have not had access to any medical texts.
Thus, it is suggested that there may be true medicinal properties in many
of the plants considered.

In addition to these 25 plants, 175 were considered for all usages ascribed
to them. Of these, 134, or 77 per cent, were used by the Maya as medicine
for specific ailments. For all but a very few plants, more than one medicinal
usage was given, and some plants had three or four medicinal usages ascribed
to them. Samples of extracts of 36 plants used medicinally were purchased
in the Merida drug store, showing a widespread use of plants for medicine
among the Maya.

Seventy -three of these 175 plants are eaten as fruits and vegetables by
the Maya, plus 33 others which are said to be food for their domestic or
wild animals. Thus, 106, or 61 per cent, of the 175 plants serve as food.
Some of these plants form the main sustenance of the Maya. For example,
maize (Zea mays L.) supplies 75 per cent of their diet. The Indians depend
greatly on honey produced from the nectar of certain trees.

Twelve per cent of the 175 plants are used for lumber and house construc-
tion purposes. In addition to these main usages, twenty-two other categories
are listed which show the extensive use of plants by the Maya Indians.

Testing the Psychology of Races

In our last report we described a modification of the McAdory Art Test
in which pictures of horses, cows, trees, clouds, and other natural objects
replaced pictures of the dresses, fences, silverware, automobiles, etc., of the
McAdory Art Test. Our modified test was given to Navajos and Dutch
whites, with the interesting result that the Navajos judged all objects from
a utilitarian standpoint, while the whites judged them more from the point
of view of art. During the current year, the text was further revised in
such a way as to eliminate the consideration of utility. For example, such
objects as belts, hats, saddles, and boots were used instead of horses and

DIVISION OF ANIMAL BIOLOGY 71

trees, etc. In this test, the subject was shown four belts or four hats which
differed in artistic value, but were the same from a utilitarian standpoint.
At the time of this writing, the results have not been analyzed.

Dr. Theodora Abel, a psychologist in New York City, has devised a test
in which the subject is asked to draw a symmetrical design, using 19 straight
lines and 6 curved lines. The author was asked to give the test to an ade-
quate number of Dutch whites in Michigan and Navajos in Arizona, which
were to serve as norms for her study on schizophrenics. Dr. Abel has com-
pleted her study, and writes as follows concerning the testing:

"Schizophrenics, whose predominant and prevailing attitude is a perse-
cutory paranoid trend, perform in a characteristic manner when asked to
make a design of limited scope. They are unable and unwilling to build up
a constructive idea about arranging straight and curved lines in a pattern
as do normal subjects, and are obsessive about following explicitly the in-
structions concerning the limitations of the task, namely employing a certain
number of lines. They do what they are told as long as the task is one of
simple understanding and recall (drawing 19 straight and 6 curved lines),
but do not carry out the other part of the task which requires some use of
thinking and imagination . . .

"We have indicated that more normal individuals, but those who have
some characteristic paranoid trends, perform more like the patients than
like normal people in making the design. We have pointed out also that a
very maladjusted Navajo Indian, who was a gifted artist, made no attempt
at making a pattern but drew the straight and curved lines linearly and
rigidly as did the schizophrenics, whereas the other Navajos tested showed
flexibility in working out definite patterns in their designs."

Dr. Margaret Curti of Columbia University and the author are cooperat-
ing in a study on young Maya children from Yucatan. The Minnesota Pre-
school tests were redesigned so as to be applicable to Maya children. Thus,
in test 3, "Naming of familar objects," instead of cups, balls, and watches,
pencils and scissors, which were called for in the American test, the Maya
children are asked to name an orange, a piece of henequen string, a stone,
and a chili pepper. The test also calls for naming parts of the body, locating
objects in pictures, vocabulary, etc. All testing was administered by Pedro
Castillo, a Yucatan schoolmaster of about fifty years of age, a man who
commands the respect of all school children. Some preliminary results of
this work are summarized by Dr. Curti as follows:

"1. The 'Minnesota-Maya Tests' as now in use in Yucatan constitute
useful material for testing 'intelligence' in young Maya children, for the
following reasons: (a) Many of the tests, and the scale as a whole, show
increasingly good performance with increase in age. (b) All of the children
who attempt the tests are able to do something with them ; and a wide range
of ability is shown, (c) A child's attack on the tests is in general rather
consistent — i.e., he can do several tests at his age level, indicating that in
general the tests are adapted to the abilities of the children. This does not
hold of all the tests; and a few of the items must be discarded as not fair to
the Maya children. But there are enough good tests to constitute an ade-
quate 'measure' of the children's ability.

72 CARNEGIE INSTITUTION OF WASHINGTON

"2. The children in general show good ability in the tests, on certain
items tending even to excel American children who have been given the same
tests. This suggests that when dealing with material familiar to them, the
'intelligence' of the Maya children is not inferior. This is a striking find
and will be of great interest to students of psychology and anthropology.

"3. There are probably more shy or uncooperative children among the
Maya group than commonly found in an American group of the same age.
For unusually shy or uncooperative children the tests do not of course
furnish estimates of intelligence. The same thing holds true of very shy
or uncooperative American children.

"4. Some individual children do outstandingly good work on these tests.
This suggests that the tests would be a useful means for helping to select
superior individuals who might be sent to school or otherwise specially
encouraged.

"5. The results so far are especially significant in that they demonstrate
the possibility of using specially adapted tests for the comparative study of
the intelligence of primitive and more advanced peoples. Test comparisons
so far made have shown marked inferiority in test performance on the part
of the more primitive of the two 'races' compared, but of late it has been
increasingly recognized that the inferiority is probably related to such factors
as unfamiliarity with the methods and materials, and shyness. In the
present study special efforts have been made to eliminate such factors as
far as possible."

DIVISION OF ANIMAL BIOLOGY 73

NUTRITION LABORATORY1

Thorne M. Carpenter, Acting Director

The early part of the year was occupied, for the most part, in an intensive
effort to complete the preparation for publication of monographs and journal
articles by Dr. Francis G. Benedict before his retirement as Director. This
was most successfully accomplished, and the several publications have gone
through the press.

The experimental work has continued largely in the same fields of research
as have already been in progress for a number of years. In spite of a consid-
erable amount of observation on the biological variations in basal metabolism,
there are still gaps in the data and excellent leads for future study, particu-
larly of those animal species in which there are large variations in size and
configuration. Conspicuous examples are found in the rabbit and the dog.
The study already made of the metabolism and the heat regulation of the
woodchuck points to the importance of continuing such investigation on
those animals, like the woodchuck, that have seasonal changes in their
metabolic levels and that seem to form a connecting link between homoio-
thermic and poikilothermic animals.

There is at present a renewed interest in bodily heat regulation, as evi-
denced by the number of recent publications concerned with the distribution
of heat elimination, the skin and the body temperature. The present increas-
ing use of methods of air conditioning, particularly air cooling (some of which
are far from satisfactory either from the physiological standpoint or from the
standpoint of comfort) , indicates the need of more knowledge of human heat
regulation in response to rapid and unusual changes in environmental con-
ditions. The past experience of the Nutrition Laboratory in the studies of
skin and body temperatures and its experimental equipment, particularly the
emission calorimeter for humans, provide conditions for a comparative study
of heat production and heat elimination which would be of value in under-
standing the physiological processes of the body when there is a necessity for
rapid adaptation to changes in environmental conditions.

Most of our food supply is in the form of carbohydrates in common foods.
An index of the supply and utilization of the foodstuffs in the body is fur-
nished by the respiratory quotient, the level of which is influenced pre-
dominantly by the carbohydrates. Consequently part of the experimental
program is to carry on such studies as may be of assistance in interpretation
of the respiratory quotient and of value in indicating the availability of
carbohydrates, both as a source for furnishing fuel for immediate combus-
tion and as a source of glycogen reserve. Several studies have been made
during the past year dealing with the factors affecting the respiratory
quotient and particularly the effects of sugars and foodstuffs on the time
relationships in the changes in the quotient and the height to which the
quotient is increased after ingestion of these foods. Such studies not only
have academic interest but also are of practical interest, especially in
medicine where there is need for an index as to the glycogen supply and the
availability of carbohydrates in the body.

1 Situated in Boston, Massachusetts.

74 CARNEGIE INSTITUTION OF WASHINGTON

STAFF NOTES

Dr. Francis G. Benedict retired on November 1, 1937, as Director of the
Nutrition Laboratory and was appointed a Research Associate of the
Carnegie Institution. Between March 2 and March 8, 1938, addresses were
given by him under the auspices of Sigma Xi at the Ohio State University,
the Michigan State College, the College of Medicine of the University of
Illinois, the University of Colorado, the University of Washington, and
Purdue University. The subject of these addresses was " Animal metabolism
from the mouse to the elephant." In some instances Dr. Benedict also gave
an additional talk on "What the research worker may learn from the
magician."

Dr. T. M. Carpenter gave a paper entitled "The effect of urea on human
respiratory exchange and alveolar air" on September 7, 1937, at the semi-
annual meeting of the American Chemical Society at Rochester, New York.
On March 11, 1938, he lectured to the students in biochemistry at the Har-
vard Medical School on "Basal metabolism and specific dynamic action."
On April 2, at the annual meeting of the American Physiological Society at
Baltimore, Maryland, he presented a paper, with Dr. C. G. Hartman of the
Department of Embryology as co-author, on "The effect of hexoses on the
respiratory quotient of the rhesus monkey." On March 30, 1938, Dr.
Carpenter was elected Vice-president of the American Institute of Nutrition
at its annual meeting, and on May 13 he was elected Chairman elect (Vice-
chairman) of the Northeastern Section of the American Chemical Society.

A conference among members of the Institution's Division of Animal
Biology was held at the Nutrition Laboratory on February 5, 1938, at which
were present A. F. Blakeslee, T. M. Carpenter, W. M. Gilbert, C. G. Hartman,
R. C. Lee, 0. Riddle, and G. L. Streeter. Guests were E. G. Ritzman and
N. F. Colovos of the Laboratory for Animal Nutrition at Durham, New
Hampshire; M. 0. Lee, H. C. Trimble, and G. B. Wislocki of the Harvard
Medical School; and H. F. Root and Priscilla White of the New England
Deaconess Hospital.

From time to time groups of students from various schools have visited the
Laboratory and been conducted around the building. These have included
students from the Harvard Medical and Dental Schools, graduate students in
nutrition from the Massachusetts State College at Amherst, and students
from Nasson College at Springvale, Maine.

INVESTIGATIONS IN PROGRESS

Observations on the marmot. The study of the metabolism of the marmot
and of factors related to the metabolism was terminated in the spring of 1937.
There remained, however, certain lacunae in the data secured, particularly
with regard to the body temperature gradient and the respiratory quotient
during hibernation. These two problems have been studied during the past
year by R. C. Lee, assisted by G. Lee.

Metabolism of the normal rabbit. The study of the heat production as
influenced by differences in size within the same species has been continued
under the direction of R. C. Lee (assisted by G. Lee, C. Hatch, and H. B.

DIVISION OF ANIMAL BIOLOGY 75

Lee) and now includes observations on rabbits ranging in weight from 1.5 kg.
(Polish) to 7 kg. (Flemish Giant). Emphasis has been laid upon the effect
of environmental temperature on the metabolism and the adaptation of the
animal to various controlled environmental conditions after living under
such conditions for a long time. A special study of the body temperature
and the factors affecting it has been made. A group of wild cottontail
rabbits have furnished considerable data for comparison of the wild with
the domestic animal.

Metabolism of the narcotized rabbit. By the use of nembutal the cell
temperature of rabbits has been lowered to approach the condition obtaining
with hibernating marmots. With rabbits thus narcotized observations on
heart rate, respiration rate, body temperature, respiratory quotient, and
metabolism have been carried out by R. C. Lee, assisted by G. Lee, for the
purpose of studying the factors that control the heat production and the
body temperature.

Basal metabolism in experimentally produced atherosclerosis. For some
time it has been known that experimentally atherosclerosis can be produced
in animals by the feeding of cholesterol and that if thyroxin or thyroid
extract is given simultaneously, atherosclerosis is not so likely to take place
or may even be prevented. This suggests that the thyroid gland may play
a role in controlling the development of this disease. For a number of years
Dr. Timothy Leary, Medical Examiner of Suffolk County, Massachusetts,
has been studying experimentally the production of atherosclerosis in rabbits
by cholesterol feeding, with special reference to its pathology. During the
past year the Nutrition Laboratory has begun a cooperative study with him
on the basal metabolism of these animals. The basal metabolism has already
been determined of a group of rabbits to be fed cholesterol and a group to
serve as normal controls. Repetition of these determinations will be made
after several months of feeding cholesterol, as a control on the level of the
thyroid activity. The basal metabolism studies have been under the super-
vision of R. C. Lee, assisted by G. Lee.

Skin temperature of domestic animals. In cooperation with Professor E. G.
Ritzman, at the University of New Hampshire, and under his direction, the
skin temperatures of a pig, a goat, a sheep, and a ram were measured under
various environmental conditions by R. C. Lee and N. F. Colovos. These
measurements contribute to a study of heat loss and the conservation of heat
by the animal body.

Metabolism studies with domestic animals. The profitable cooperative
research on the metabolism of domestic animals, which has been carried on
for a number of years with Professor E. G. Ritzman at the University of
New Hampshire, was terminated January 1, 1938, so far as direct connection
administratively between the Nutrition Laboratory and the University of
New Hampshire is concerned. Professor Ritzman was then appointed Re-
search Associate of the Carnegie Institution of Washington.

Metabolism studies on the Macacus rhesus. The metabolism measure-
ments on the Macacus rhesus, which have been carried on for several years
with the colony at the Department of Embryology at Baltimore with the
cooperation of Dr. George L. Streeter and Dr. Carl G. Hartman, were brought

76 CARNEGIE INSTITUTION OF WASHINGTON

to an end on October 1, 1937. The calculations and completion of the ma-
terial for a report are in progress at the present time.

Respiratory quotient of the Dalmatian dog. The protein metabolism of
the Dalmatian dog is characterized by a much larger urinary excretion of
uric acid as an end product of the metabolism than occurs with any other
breed of dog. Through the cooperation of Dr. Harry C. Trimble of the De-
partment of Biochemistry of the Harvard Medical School, and with the as-
sistance of B. James and M. Stankard, metabolism studies have been made
on a dog of this breed with particular reference to the partition of the total
metabolism in relation to the respiratory quotient and the nitrogenous ex-
cretion in the urine during fasting and after feeding of meat.

Effect of ingestion of hexoses on the respiratory quotient of the Macacus
rhesus. An unusual opportunity for a study of the effect of sugars on the
respiratory quotient of primates was afforded by the colony of rhesus monkeys
at the Department of Embryology at Baltimore. After the measurements of
basal metabolism were terminated, a special intensive series of respiration
experiments was made in cooperation with Dr. C. G. Hartman, in which the
respiratory quotients were determined after ingestion of glucose, fructose, or
galactose. In the experiments with galactose the urinary excretion of the
sugar was also determined. The respiration experiments were made by B.
James. A preliminary report (see page 82) of this research has been
presented to the American Physiological Society.

Effect of ingestion of hexoses on the respiratory quotient of the goat.
There is evidence that metabolism of carbohydrates in the ruminant is differ-
ent from that in other animal species, as is shown by the marked production
of methane when ruminants are on full feed. In the general investigation on
the effects of sugars on the respiratory quotients of animals it is obvious that
this species should be included. Through the cooperation of Professor Ritz-
man, studies on the effect of ingestion of hexoses on the respiratory quotient
of the goat have been initiated and are in progress.

The electrical method of gas analysis. For a number of years it has been
evident that the immediate need in the advancement in the technique of
metabolism studies is for a more rapid method of determination of the
composition of the gases that have to be studied in measurements of respira-
tory exchange. During the past year an apparatus has been developed and
described by Professor A. K. Noyons, of the University of Utrecht, Holland,
for the determination of the changes in composition of gases by measurement
of changes in resistance of a heated wire due to the changes in the surround-
ing gaseous atmosphere. Construction of a similar apparatus has been
started at the Nutrition Laboratory by V. Coropatchinsky, for the purpose
of comparing this apparatus with the standard form of gas analysis apparatus,
in which the composition of gases is determined by volumetric analysis.

Prevention of respiratory failure in newborn infants. Dr. Priscilla White,
of the Joslin Clinic and the New England Deaconess Hospital, in studying
the prevention of respiratory failure in newborn infants of diabetic mothers,
has continued the use of the Nutrition Laboratory's helium-oxygen chamber.
R. C. Lee and G. Lee have assisted in this work.

Metabolism in diabetes. In cooperation with Dr. Howard F. Root of the

DIVISION OF ANIMAL BIOLOGY 77

New England Deaconess Hospital and with the assistance of R. C. Lee and
B. James, a special study was made of a patient who not only had diabetes
but also had had acromegaly at some time during the past. The study of the
metabolism during diabetic coma is to be continued as opportunity offers.

Maximum temperature of expired air as an index of body temperature.
The apparatus for determining the maximum temperature of the expired air
(mentioned in Year Book No. 34, p. 65) has been further developed and the
relationship of the maximum temperature of the expired air to the body
temperature established. This apparatus is particularly adapted for meas-
uring the body temperatures of large groups of humans in that measure-
ments can be made at the rate of four per minute. Numerous measurements
of normal subjects were made at the Nutrition Laboratory, and a special
series of measurements of patients with artificially produced fever was made
at the Boston Psychopathic Hospital through the cooperation of Dr. H. C.
Solomon and Dr. I. Kopp. This research was conducted by R. C. Lee, as-
sisted by H. B. Lee.

Effect of ingestion of foods on the human respiratory quotient. The car-
bohydrates in the human diet are not, for the most part, derived directly
from pure sugars but from mixtures of simple and hydrolyzable sugars
and starches. Such combinations are found in vegetables, cereals, fruits, and
nuts. The rise in the respiratory quotient is one index of the availability of
carbohydrates to the body and the rapidity with which they are burned.
Experiments were made on the changes in the respiratory quotient with
respect to height of the rise and the time relationships, in which single
portions of common foods (cooked and raw vegetables, bread, nuts, and
fruits) were given that contained approximately 25 grams of carbohydrates
each. Control experiments with 25 grams of glucose or of cane sugar served
for comparison. Samples of the foods given are to be analyzed for reducing
sugars, hydrolyzable sugars, and starches, to compare with the actual changes
in respiratory quotient and to determine which of the carbohydrates are
most effective in causing a rise in the respiratory quotient. The respiration
experiments are being carried out by B. James and the chemical analyses by
M. Stankard.

LITERARY WORK

A paper on "The maximum temperature of expired air as a rapid measure
of human body temperature" has been written by Dr. and Mrs. Benedict and
Mr. and Mrs. R. C. Lee and has been accepted for publication by the New
England Journal of Medicine. A manuscript on the body temperature of
the normal rabbit and factors affecting it is in the process of preparation by
R. C. Lee. The large amount of proofreading and editorial work has had
the capable supervision of the editor, Elsie A. Wilson.

PUBLICATIONS

(1) The basal metabolism and urinary nitrogen excretion of Chinese, Manchus, and others
of the Mongolian race. Francis G. Benedict, Lan-Chen Kung, and Stanley D.
Wilson. Chinese Jour. Physiol., vol. 12, pp. 67-100 (1937).

Basal metabolism measurements on 120 adult Mongolians, chiefly Chinese and
Manchus, showed as with other human races an increase in total heat production
with increasing weight, a decrease in heat production per kilogram the larger the

78 CARNEGIE INSTITUTION OF WASHINGTON

individual, a decrease in total heat production with advancing age among subjects
of the same weight, and a lower metabolism of the women than of the men. Pulse
rates and nitrogen output per kilogram of body weight were in general the same
as noted with Caucasians. The decrease in total heat production per year increase
in age averaged about the same for the male Chinese as for Caucasian men (7 calories)
but averaged 5 calories for the Chinese women as compared with 2.3 calories for
Caucasian women. No marked influence of Western civilization upon the metabolism
of those Chinese who had adopted Western ways of living was apparent. The basal
metabolism of these Chinese as a whole was, by every method of comparison, lower
than that noted with Caucasians, the difference being more pronounced with the
men than with the women.

(2) Die Bedeutung des Korperfettes filr die Warmebildung im Organismus. Francis G.

Benedict and Robert C. Lee. Biochem. Ztschr., vol. 293, pp. 405-409 (1937).

Within the weight range from 2.5 to 7.5 kg. adult geese had a total heat produc-
tion that increased in a straight-line relationship with the increase in weight. Inas-
much as in the surfeit feeding of adult geese the protein content of the body is only
slightly increased, the increase in heat production of these geese with increasing
weight was the result of an increased storage of fat. This finding is supported by
observations on the basal metabolism and body composition of 8-g., 21-g., and 60-g.
mice. Body fat should, therefore, not be considered as metabolically inert but as an
energy-demanding substance.

(3) Basal metabolism of rats in relation to old age and exercise during old age. Francis

G. Benedict and Henry C. Sherman. Jour. Nutrition, vol. 14, pp. 179-198 (1937).

With a group of adult rats (non-exercised) of different ages but of the same weights
the basal 24-hour heat production was somewhat higher in old age than in middle
life. With a group of adult rats (non-exercised) of different weights as well as
ages, however, the heat production was relatively constant at the older ages. The
total heat production of any one rat decreased slightly with advancing age, but at
the same time there was a relatively larger (although also small) decrease in body
weight, so that the metabolism per unit of weight and per unit of surface area in-
creased slightly. The body temperature tended to decrease in old age (after 800
days of age), and in very advanced age the decrease amounted to about 2° C.
Middle-aged male rats, not previously exercised, could not adjust themselves to
strenuous exercise begun so late in life, lost weight rapidly, and usually died. Middle-
aged female rats, not previously exercised, were apparently benefited by the exer-
cise, which tended to lower their basal metabolism. It is suggested that the organism
of the exercised rat is freed by muscular exercise from a middle-age restlessness or
chronic useless tenseness and is able to relax better in rest periods.

(4) Race: A factor in human metabolism. Francis G. Benedict. Proc. Amer. Philos. Soc,

vol. 78, pp. 101-110 (1937).

This paper summarizes the metabolic findings of a racial survey made by the
Nutrition Laboratory and its collaborators. Oriental races in general were found
to have a metabolism somewhat lower than that of Caucasians in the United States.
South Indian women in Madras had a metabolism 17 per cent below the Caucasian
prediction standards, and this was further depressed about 10 per cent during deep
sleep. In striking contrast to the low metabolism of the majority of the Oriental
races were the high metabolism of the Maya (+8 per cent) in Yucatan and the Miao
males (+16 per cent) in Szechwan, China, although in both instances low pulse rates
were observed. With Manchus of the laboring class, both males and females, lower
values for total heat production were found than with Chinese laborers of the same
weight, age, and sex. This survey has established that there are marked differences

DIVISION OF ANIMAL BIOLOGY 79

in the basal metabolism of different human races, probably ascribable solely to the
racial factor and not to differences in climate and diet, and that there may even be
a racial difference in metabolism within the Oriental race itself.

(5) Lipogenesis in the animal body, with special reference to the physiology of the goose.

Francis G. Benedict and Robert C. Lee. Carnegie Inst. Wash. Pub. No. 489
(1937) . ix + 232 pp., 30 figs., 35 tables.

To study the metabolism during the transformation of carbohydrate into body fat
(lipogenesis) adult geese were fed surfeit amounts of a corn-meal mixture, following
which measurements were made of the respiratory exchange and the heat produc-
tion. The latter was determined directly by means of an emission calorimeter, de-
scribed in detail. The respiratory exchange measurements, the techniques for which
are also described, included the oxygen consumption, the carbon dioxide elimination,
the cleavage carbon dioxide, and the respiratory quotient. The physiology of the
goose was also studied under normal basal conditions and during prolonged fasting,
and observations were made of the rectal temperature, heart rate, respiration rate,
insensible perspiration, water-vapor output, chemical composition of the body, and
zone of thermic neutrality. By surfeit feeding of carbohydrate the oxygen con-
sumption of the goose may be increased 50 to 100 per cent and the carbon dioxide
elimination 100 to 400 per cent. The respiratory quotient may increase to 1.48.
Maximum values for all three factors and also for cleavage carbon dioxide occur
within 1 to 3 hours after surfeit feeding and persist for about 3 hours, but the usual
basal values are found again within 24 hours. According to the data obtained in
the calorimeter experiments, when carbohydrate is converted into fat after surfeit
feeding and the respiratory quotient remains at a constant high level of about 1.40,
the relationship between the simultaneously measured oxygen consumption and the
heat production is the same as that during the combustion of pure carbohydrate at
a respiratory quotient of 1.00. Hence when the respiratory quotient is above 1.00,
the heat production can be calculated indirectly with sufficient accuracy from the
measured oxygen consumption by use of the factor of 5.047 calories per liter of
oxygen.

(6) Effects of thyroidectomy and thyroid feeding in geese on the basal metabolism at dif-

ferent temperatures. Milton O. Lee and Robert C. Lee. Endocrinology, vol. 21,
pp. 790-799 (1937).

The metabolism (per lOw2/3) of twelve normal geese was 25 per cent higher at
11° C. than their basal rate at 23° C. Four of these geese, after thyroidectomy, had
a metabolism, on the average, 51 per cent higher at 11° C. than their average level
at 23° C. The metabolism of these thyroidectomized geese was 33 per cent lower
at 23° than that of the normal birds but only 15 per cent lower at 11° C. The
thyroidectomized goose can make metabolic adjustments to low environmental
temperatures as great in magnitude as the normal goose. The thyroid gland is,
therefore, not necessary to the goose for thermogenesis in adaptation to a cold
environment.

(7) Further observations on the physiology of the elephant. Francis G. Benedict and

Robert C. Lee. Jour. Mammal., vol. 19, pp. 175-194 (1938).

Supplementing the detailed study of the physiology of the elephant reported in
1936 (Carnegie Inst. Wash. Pub. No. 474), further observations were made, par-
ticularly to fill obvious lacunae in the first investigation. These deal with the
muscular activity of the elephant, the sleeping positions assumed, the teeth, the
habits of eating and chewing, the hearing, the reaction to rats and mice, the maxi-
mum possible weight, measurements of height, microscopic examinations and tem-
perature measurements of feces and urine, skin temperature measurements, determi-

80 CARNEGIE INSTITUTION OF WASHINGTON

nations of methane in the intestinal gases, and observations on respiration rate and
heart rate. Men in charge of zoological parks and circuses are urged to notify
scientists when elephants are to be killed, so that further studies can be made when
these animals are dissected.

(8) The nutritional physiology of the adult ruminant. Ernest G. Ritzman and Francis G.

Benedict. Carnegie Inst. Wash. Pub. No. 494 (1938). vi + 20O 7 p., 3 pis., 3 figs.,
55 tables.

In this monograph are reported the results of a cooperative investigation by the
New Hampshire Agricultural Experiment Station and the Nutrition Laboratory,
dealing primarily with the nutritional physiology of the cow but supplemented by
observations on steers, bulls, sheep, goats, and horses. Eleven cows were studied
under maintenance conditions of feeding, over periods ranging from 4 months to
nearly 4 years, and with these animals 49 digestion balance experiments (each one
month long) were made. At the end of each digestion experiment the respiratory
exchange was measured, first with the cows on feed and then on the fourth and
fifth days of fasting. The rations fed were hay alone (six kinds, of early and late
cutting), concentrate alone (corn meal or linseed oil meal), or a mixture of con-
centrate and bran. The cows (Holsteins and Jerseys) were all adults and in most
instances dry and not pregnant, although a special study was made of two cows
during pregnancy and lactation. The first section of the monograph deals with
digestibility of roughages and of concentrates, weight and character of fill, methane
production, chemical composition of excreta, nitrogen and energy balances, water-
vapor output, insensible perspiration, heart rate, respiration rate, and body tem-
perature. In the second section the conditions prerequisite for basal metabolism
measurements on ruminants are outlined and the results of such measurements on
the cows are discussed. Great variability was noted in the metabolism of one and
the same cow (dry and not pregnant), changes of 30 to 74 per cent occurring within
as short a time as six weeks without marked difference in nutritive condition. The
cause of this variability is considered to be of hormone origin, due to selective breed-
ing for milk production. The percentage increases in metabolism above the basal
level due to the stimulating effects of the ingestion of the different roughages (pre-
dominantly carbohydrate in nature) were as great with these cows as the increases
following protein ingestion noted with dogs and humans. In the last section of the
book the factors to be considered in evaluating the utilization of food energy by
cattle are discussed, especially the dynamic stimulus of food and the great varia-
bility in basal metabolism. The digestible energy, the net energy, and the meta-
bolizable energy as measured in the digestion balance experiments are also discussed,
and in the concluding pages there is a brief consideration of the efficiency of
metabolizable energy for maintenance and for milk production.

(9) Hibernation and marmot physiology. Francis G. Benedict and Robert C. Lee. Car-

negie Inst. Wash. Pub. No. 497 (1938). x + 239 pp., 2 pis., 11 figs., 58 tables.

A metabolic study of the marmot was made to secure information regarding the
physiology of the animal itself and for comparison with other warm-blooded animals
that do not hibernate and with cold-blooded animals, for in its awake and asleep
periods it resembles somewhat these two types of animals, respectively. Measure-
ments of body weight changes, insensible perspiration, heart and respiration rates,
rectal temperature, respiratory exchange, and water-vapor output were made on
48 marmots, at different environmental temperatures, in the non-hibernating and
hibernating states, and in the transitional stages of entering and awakening from
hibernation. Several marmots were drugged with nembutal and subsequently ex-
posed to a cold environment, others were subjected to carbon dioxide narcosis and

DIVISION OF ANIMAL BIOLOGY 81

cold, and the measurements on these were compared with those on the animals
hibernating under normal conditions. The urines voided by four marmots while
fasting and hibernating were analyzed to determine the partition of urinary nitrogen.
During hibernation there was no marked change in the character of the respiratory
exchange, the true combustion respiratory quotient was one of fat, and the protein
metabolism underwent no qualitative alteration. When not hibernating, the marmot
has a labile basal heat production and rectal temperature, but when its body tem-
perature is 36.9° C. its basal metabolism averages about 400 calories per 10w2/3 per
24 hours. This is much higher than that of any cold-blooded animal of the same
size at a body temperature of 37° C. but is considerably lower than the metabolism
of other warm-blooded animals of the same size thus far studied. The hibernating
marmot resembles the cold-blooded animal in that, when exposed to a low environ-
mental temperature, its rectal temperature becomes very low and its respiration
rate slow, but its heat production per lOw2/3 even at the minimum level is two or
three times that of a snake of the same size having the same low body temperature.
The causes and theories of hibernation are discussed, and a digest of the main find-
ings of the investigation is presented.

(10) Vital energetics: A study in comparative basal metabolism. Francis G. Benedict.
Carnegie Inst. Wash. Pub. No. 503 (1938). vii + 215 pp., 46 figs., 4 tables.

The basal metabolism measurements on all the animal species that have been
studied at the Nutrition Laboratory during the past three decades are analyzed in
this report from the standpoint of comparisons within the same and between dif-
ferent species. Only adult animals are considered. These ranged in size from the
8-g. dwarf mouse to the 4000-kg. elephant. The prerequisites for comparable meas-
urements of basal heat production are outlined, and consideration is given to the
bases for intraspecific and interspecific comparisons of animals of different sizes,
with particular reference to the metabolically inert factors affecting body weight and
the problems of measuring or calculating the true surface area of the body. For
each warm-blooded species a chart is given, in which the total 24-hour heat produc-
tion of each animal measured is plotted with reference to its body weight and a
curve is drawn through the plotted data to indicate the general trend of the metabo-
lism with increasing weight. These intraspecific comparisons represent eighteen
species of mammals, including humans, seven species of domesticated birds, and
several wild birds. The interspecific comparisons are based upon a series of charts
for progressive weight groups and also for the entire weight range from 8 g. to 4000
kg., in which are assembled the curves representing the trends of the average metabo-
lism of the different species referred to weight and expressed as total heat production,
heat production per kilogram, and heat production per lOw2/3. The measurements
at environmental temperatures of 16° and 28° C. are compared, and there is a
critique of the surface area concept. The measurements are also referred to different
powers of the body weight. Finally, warm-blooded animals are compared with cold-
blooded animals both at low cell temperatures and at 37° C. Emphasis is laid upon
the value of basing metabolism comparisons upon the total heat production of species
of the same body weight, thus eliminating the problem of how to equalize differences
in weight. Discussion is given of the factors that may contribute to metabolic
differences within and between species, such as body structure, composition, and
covering, cell temperature, cell enzymes, brain weight, and blood. It is recom-
mended that one should turn from a consideration of heat loss to a consideration
of heat production, that the lack of uniformity in heat production should be
recognized, and that the differences in metabolic intensity or vital energetics should
be associated with differences in body configuration and composition and with differ-
ences in the morphology, chemistry, and particularly the distribution of the blood.

82 CARNEGIE INSTITUTION OF WASHINGTON

(11) The partition of urinary nitrogen of fasting and hibernating woodchucks (Arctomys

monax). Thorne M. Carpenter. Jour. Biol. Chem., vol. 122, pp. 343-347 (1938).

One specific detailed example is given of the results of a study of the partition
of urinary nitrogen in the urine of a marmot. The details of other studies are given
in the monograph cited on page 80 of this report.

(12) Effects of hexoses upon the respiratory quotient of the rhesus monkey. Thorne M.

Carpenter and Carl G. Hartman. Amer. Jour. Physiol., vol. 123, p. 32 (1938).

Abstract. (See page 76.)

(13) The effect of urea on the human respiratory exchange and alveolar carbon dioxide.

Thorne M. Carpenter. Jour. Nutrition, vol. 15, pp. 499-512 (1938).

Ingestion of 30 and 40 g. of urea caused marked rises in the alveolar carbon dioxide
and in the respiratory quotient during 3 to 3% hours after ingestion, but no change
in the oxygen consumption, as compared with these same factors in control experi-
ments. The simultaneous increases in alveolar carbon dioxide and respiratory quo-
tient are the result of the alkalosis following the ingestion of urea. As the alveolar
carbon dioxide is also increased by the gastric secretion following the ingestion of
protein, there may be two causes for the alterations in the respiratory quotient from
the true respiratory quotient of protein, one the gastric secretion containing hydro-
chloric acid and the other the urea that ultimately results as a metabolic product
of the transformations of protein in the body.

(14) The effect of ingestion of alcohol on human respiratory exchange (oxygen consumption

and R. Q.) during rest and muscular work. Thorne M. Carpenter and Robert C.
Lee. Arbeitsphysiologie, vol. 10, pp. 130-157 (1938).

Measurements of the respiratory quotient and the oxygen absorption after inges-
tion of 30 and 50 cc. of alcohol, respectively, indicated that the metabolism of
alcohol proceeded at about the same rate, irrespective of whether the subject was
resting or exercising on a bicycle ergometer. That muscular work does not increase
the combustion of alcohol was also demonstrated by the calculations of the changes
in the katabolism of carbohydrate and fat in the periods of work and recovery
following alcohol ingestion. There was no summation of the separate effects of
alcohol and muscular work when both these factors were superimposed upon the
basal metabolism. The efficiency of performance of work (relation between the
heat equivalent of the work performed and the energy expenditure) was not the
same in experiments with alcohol ingestion as in experiments without alcohol in-
gestion.

(15) The effect of muscular work on the amounts of alcohol in urine, expired air, and blood,

after its ingestion by man. Thorne M. Carpenter and Robert C. Lee. Arbeits-
physiologie, vol. 10, pp. 158-171 (1938).

Exercise on a bicycle ergometer at varying rates of speed for periods of 30 minutes
to 2 hours after ingestion of 30 and 50 cc. of alcohol did not appreciably alter the
concentration of alcohol in urine, blood, or expired air, or the amount of alcohol
eliminated per liter of carbon dioxide exhaled, as compared with these same factors
during rest. The amounts of alcohol in the ventilating air current of the respiration
apparatus were greater during exercise than during rest and were greater the severer
the work, because of the increased total ventilation of the lungs. However, when
the work ceased, the amounts approached those found in the same time interval
after ingestion in the rest experiments. In the rest experiments from 0.4 to 0.7 per
cent of the total alcohol ingested was eliminated in the ventilating air current and
from 0.8 to 1.6 per cent was eliminated in the urine and expired air. In the work
experiments these percentages were 0.9 to 1.6 and 1.1 to 2.1, respectively. The

DIVISION OF ANIMAL BIOLOGY 83

disappearance of alcohol through these paths plays only a small role in reducing
the amount of alcohol in the body.

(16) The effect of muscular work on the metabolism of man after the ingestion of sucrose
and galactose. Thorne M. Carpenter and Robert C. Lee. Arbeitsphysiologie,
vol. 10, pp. 172-187 (1938).

Measurements of the respiratory exchange were made in 3-hour experiments after
ingestion of 70 g. of sucrose or 50 g. of galactose, with the subject at rest and
at work. The exercise (pedaling a bicycle ergometer) resulted in a greater combus-
tion of cane sugar but not of galactose. It is questionable whether muscular work
has any effect on the metabolism of galactose except apparently to accelerate the
reaction after the ingestion of the sugar. There was no summation of the effect of
the ingestion of the sugar (either sucrose or galactose) at rest and the effect of
muscular work without sugar when the sugar ingestion was accompanied by work.
The efficiency of performance of work was better when sugar was ingested than
when it was not and was slightly better after galactose than after sucrose. More
of the ingested sugar was utilized in the more intense work.

84 CARNEGIE INSTITUTION OF WASHINGTON

TORTUGAS LABORATORY

D. H. Tbnnent, Executive Officer

Paul S. Conger, Assistant Executive Officer

During the summer of 1938 the Tortugas Laboratory was open from June 2
to August 9.

The following investigators studied at the Laboratory during the season:

P. L. Bailey, Jr., College of the City of New York. Regeneration in sabellids. June

30 to August 9.
N. J. Berrill, McGill University. Budding in polystyelid ascidians. June 16 to June

28.
F. J. Brinley, North Dakota Agricultural College. Origin of muscular movements

in fish embryos. June 16 to August 9.
Leonard B. Clark, Union College. Swarming of the Atlantic palolo. Habits of the

basket star. June 16 to July 26.
Paul S. Conger, U. S. National Museum and Carnegie Institution of Washington.

Investigations on diatoms. June 2 to August 9.
B. R. Coonfield, Brooklyn College. The development and coordination of melano-

phores in embryos of Pomacentrus. June 30 to August 9.
Hugh H. Darby, College of Physicians, Columbia University. Continuation of studies

of regeneration in Crustacea. June 30 to August 9.
John H. Davis, Jr., Southwestern College. Studies of mangroves and changes of

strand flora. June 16 to June 28 and July 28 to August 9.
Walter N. Hess, Hamilton College. Reactions to light and the photoreceptors in the

spiny lobster. Habits of the basket star. Swarming of the Atlantic palolo.

June 16 to July 28.
Norris Jones, Swarthmore College. Investigations on ascidians. June 30 to July 26.
Balduin Lucke, The School of Medicine, University of Pennsylvania. Studies on

tumors in cold-blooded vertebrates. June 2 to June 28.
Gordon Marsh, State University of Iowa. Further studies on the electrical behavior

of Valonia. June 2 to August 9.
Paul A. Nicoll, University of Chicago. The response of ascidian larvae toward certain

hormones. June 30 to August 9.
Fernandus Payne, Indiana University. Study of the effect of anterior pituitary

hormones on the development and discharge of the sex cells in Ptychodera baha-

mensis. Observation of Amphioxus larvae. June 30 to August 9.
Harold H. Plough, Amherst College. Investigations on ascidians. June 30 to July 28.
Gordon A. Riley, Yale University. Study of the quantity of plankton in tropical

waters. July 14 to August 9.
Vance Tartar, Yale University. Regeneration in the starfish Linckia and in the

protozoan Condylostoma. June 30 to August 9.
D. H. Tennent, Bryn Mawr College. Effect of intensity of light on photodynamic

reactions. June 16 to July 28.

Regeneration in Sabellids
P. L. Bailey, Jr.

The problem originally intended was a study of the effect of chemical solu-
tions on regeneration in the littoral oligochaete, Pontodrilus, which has pre-
viously been reported as remarkably adjusted to marine existence. The
organism proved not to be especially suited to experimental work with solu-
tions. Mortality of individuals kept in sea water, or in sea-water solutions

DIVISION OF ANIMAL BIOLOGY 85

of dinitrophenol, colchicine, and thyroxine, was very great; regeneration of
lost parts was too slow to be of value in the time available; and failure of
the wound to close properly caused in many control and experimental animals
a peculiar bulbous abnormality, without growth of new segments.

The sabellids (genera and species of which I have not completely identi-
fied to date) found plentifully in the moat at Fort Jefferson, however, proved
to be far more satisfactory. The major portion of the work was spent ad-
justing different strengths of solution to these worms. Individuals in which
40 to 50 posterior segments had been amputated failed to regenerate lost seg-
ments until after 15 days when kept in a solution of 1 grain of colchicine in
1 liter of sea water. Controls in pure sea water began to regenerate lost
segments in 3 days. In less concentrated solutions the rate of regeneration
was less retarded. Individuals were fixed at various stages of regeneration
with the hope that histological study of the effect of the chemical on the cells
will reveal further facts concerning the origin of the new tissues in the re-
generative process.

A portion of the time was spent in observation and experiments on the
tube-forming mechanisms of these same sabellids. It is hoped that a more
detailed description of the anatomy and physiology of the process can be
given than has heretofore been presented, after further experiments can be
made and a histological study of preserved material can be completed.

Budding in Polystyelid Ascidians
N. J. Berrill

The investigation relates to the general problem of the nature of inherent
organization manifest in bud rudiments and regeneration blastemas. Such
anlagen are apparently undifferentiated as wholes and consist usually of
unspecialized cells. Polystyelid ascidians represent ideal material for study-
ing this problem inasmuch as on the one hand they form a compact natural
group with highly distinctive larval, postlarval, and adult characters, and on
the other vary considerably in colony form and size, in size of constituent
zooids, and in time sequences of asexual reproduction. Material was collected,
studied alive, and preserved for more detailed investigation, of the forms
Polyandrocarpa tincta, Symplegma viride, and Botryllus nigra. It was found
that the area of the bud rudiment relative to the size of the parent zooid at
the time of its appearance was closely related to the size of mature zooids and
the general nature of the colony. It is also evident that the bud rudiment
must be regarded as an integral part of the individual organization, and as
such its development as a part of an individual is strictly comparable with
features such as gill slits or heart. Further, in Botryllus at least, the abso-
lute size of a bud rudiment determines the extent to which mature or im-
mature gonads will develop at a time when the rudiment consists of a two-
layered disk of unspecialized epithelial cells of ectodermal origin, irrespective
of the nutritive supply of the developing bud. It is hoped that further study
of this and similar material will show clearly the validity of the field or
Gestalt concept of organization when applied to blastemas exhibiting no
visible differentiation either as wholes or in their constituent cells.

86 CARNEGIE INSTITUTION OF WASHINGTON

Study of the Origin of Muscular Movement in Fish Embryos

Floyd J. Brinley

The work here reported was done at the Tortugas Laboratory from June
16 until August 9. It is a continuation of a general problem on the relation
of innervation to the origin of the heart beat, peristalsis in the alimentary
canal, body and fin movement. The organisms used were the embryos and
newly hatched larvae of Pomacentrus leucostictus and embryos of the nurse
shark.

Muscular contraction or peristalsis of the smooth muscles of the alimen-
tary canal starts in Pomacentrus embryos two or three days prior to hatch-
ing. It is first observed in the fore- and hind-gut and later develops in the
mid-gut. Contractions occur in the fore-gut at a definite rhythm of about
24 beats per minute. Peristalsis originates in the anterior region and passes
caudad, where it ceases before entering the mid-gut. Contractions of the
hind-gut occur at irregular intervals and may originate at the junction with
the mid-gut or at the posterior end. Contractions of the mid-gut occur less
frequently and at irregular intervals. These three regions of the alimentary
canal in the embryos and newly hatched larvae behave as separate physiologi-
cal units and are independent of each other in regard to muscular activity.

In older larvae, after complete absorption of the yolk, the definite rhythm
of contraction of the fore-gut is replaced by a much slower wave-like move-
ment which occurs at irregular intervals. The amplitude of contractions of
the mid- and hind-gut in the older embryos is greater than in the younger
stages, and peristaltic waves which originate in the mid-gut usually continue
to the hind-gut.

Injections of atropine sulfate solution (0.05 to 0.1 per cent) or ergotoxin
(0.1 per cent), which depress the parasympathetic and sympathetic nervous
systems respectively, have no effect on the muscular movement of the ali-
mentary canal of the embryos or day-old larvae. Injections of atropine into
older larvae depress peristalsis and constrict the entire gut. Ergotoxin in-
creases muscular activity in all portions of the alimentary canal in the older
embryos and dilates the mid- and hind-gut.

These reactions indicate that muscular contractions of the smooth muscles
originate within the muscle but are soon controlled by the ingrowth of the
autonomic nerves.

In the nurse shark body movement is first observed in 6-mm. embryos.
Microinjections of curare (which blocks the transmission of impulses from
motor nerves to striated muscles) does not affect muscular activity until the
embryos have reached a length of 18 mm. In embryos from 18 mm. to 48
mm., curare reduces body movement to a series of single twitches at definite
intervals varying from a few seconds to two minutes. In embryos larger
than 48 mm. the drug completely blocks all impulses or reduces activity to
slight twitches at several -minute intervals.

It appears from these results that muscular contraction of striated muscles
originates in the muscle and the ingrowth of motor nerves takes place between
18 and 48 mm. During this stage body movement is largely due to impulses
coming from the nervous system. When these impulses are blocked by

DIVISION OF ANIMAL BIOLOGY 87

curare, spontaneous contractions of the muscles continue at a definite rhythm
which probably is a fundamental property of all muscles. In embryos larger
than 48 mm. the stimulant for contraction arises entirely in the nervous
system, and conditions within the muscles are not suitable for spontaneous
contractions.

A study of the effect of caffeine on the rate of heart beat in shark embryos
indicates that the vagus makes contact with the heart when the embryo is
about 54 mm. in length.1 Prior to that stage, caffeine has no effect on the
rate of heart beat, but in older embryos the heart shows a decided irregu-
larity in rhythm within 2 minutes after injections of caffeine. Digitalin
(0.005 to 0.1 per cent) reduces the rate of the prevagus heart, which results
in stoppage within 10 to 15 minutes after injection. However, digitalin pro-
duces a slight increase in the rate of the innervated heart immediately after
injection. This increase passes into a depression and finally the heart stops
in diastole.

A large number of shark embryos were fixed for embryological studies.

Observations on the Atlantic Palolo
Leonard B. Clark

Rocks sterilized and planted in 1937 on West Loggerhead and Bird Key
reefs yielded young worms but no sexually mature individuals. This seems
to indicate that the palolo must be more than one year old before sexual
maturity.

With the cooperation of the lighthouse staff on Loggerhead Key, palolo
worms were collected at frequent intervals from September 1, 1937 to June 1,
1938. This material will allow studies to be made of the regeneration and
development of the sexual ends.

During the summer of 1938, twelve experiments on the effect of artificial
light were carried out. By adding artificial illumination to moonlight or
covering the floating cars containing the worms from moonlight, it has been
found that the time of swarming was seriously disturbed. Swarming epitokes
were secured at sunset, in the morning up to 10:30 a. m., and at times other
than when the worms swarmed naturally. However, on July 3, when the
natural swarm was very abundant over West Loggerhead reef, a single
epitoke was found in each of four cars, each car having been submitted to a
different light procedure. Also on July 9 a swarm occurred in each of seven
different cars, likewise having different illumination. Thus, although the
amount and duration of illumination does influence swarming, the possibility
of a hormonal substance diffusing in the water cannot be entirely ruled out.

Metabolism experiments were carried out with parts of mature worms to
determine any metabolic gradient which might be present. Usually the com-
plete worm was divided into five parts. The first consisted of the anterior
half of the atoke, the second of the posterior half of the atoke, the third of
the anterior half of the sexual portion of the epitoke, the fourth of the
posterior half of the sexual portion of the epitoke, and the last of the asexual
posterior portion of the epitoke.

1 Brinley, Physiol. Zool., vol. 4, pp. 527-537 (1932) .

88 CARNEGIE INSTITUTION OF WASHINGTON

Almost invariably the order of decreasing metabolic rates for the above
pieces was 5, 3, 4, 1, 2. In every case the asexual posterior tip of the epitoke
had the highest metabolism. This may be significant in view of the fact that
the sexual end swims with the posterior end foremost and the swimming move-
ments originate at the posterior end.

Swarming of the Palolo Worm (Eunice fucata) under Natural Con-
ditions with Observations on Reactions of Free Living Sexual Ends

Leonard B. Clark and Walter N. Hess

Systematic daily towings were made over West Loggerhead and Bird Key
reefs from June 20 to July 25, 1938. Over West Loggerhead reef, newly laid
palolo eggs were found daily from June 21 to July 4 and on July 7, 11, 14,
15, with eggs fairly numerous on June 22 and very abundant on July 3. On
these latter two dates swarming epitokes were observed.

Over Bird Key reef newly laid eggs were found on June 23 and daily from
June 28 to July 5, July 7 to 11, and July 13 to 16 inclusive. An immense
swarm occurred on July 15. On June 24 and July 16 freshly laid eggs were
fairly numerous but on the other days eggs were few in number.

The third quarter of the June moon occurred on June 21, the first and
third quarters of the July moon occurred on July 4 and 20 respectively.
Unlike any previous record of swarming, the great swarm over Bird Key
reef on July 15 occurred five days before the third quarter of the moon.

Comparative studies were made of worms in rocks from West Loggerhead
and Bird Key reefs. In general, as the total number of eggs laid increased,
the percentage of worms with sexually mature epitokes decreased.

During the swarms over West Loggerhead reef observations were made
on the time of onset of the swarm, progress of the swarm, and intensity of
light causing bursting of the epitokes with release of sex products. In the
laboratory studies were made on threshold intensity for orientation of free-
swimming epitokes.

In the swarm on the night of July 2 and morning of July 3 the first epitoke
was observed at 9:30 p. m. The number of swarming individuals increased
to a maximum at 3:40 a. m. and then decreased slowly to sunrise. After
sunrise the decrease in numbers was rapid with the last epitoke observed
bursting at 6:09 a. m., when daylight reached an intensity of 1095 foot-
candles. Sexually exhausted individuals were swimming until after 7 :00 a. m.

During the early part of the swarm males predominated, while in the later
phases females were more numerous.

Swarming epitokes varied more than a thousandfold in the intensity of
light necessary to cause bursting. The intensity necessary is related to the
rate of increase of intensity, degree of dark adaptation, and the length of
time after the epitoke became free.

Swarming epitokes orient to light, the threshold varying from 0.0005 to
0.01 foot-candle. Individuals swim in a straighter path with smaller spirals
in a strong light than in weaker illumination.

Any piece of epitoke long enough to swim will orient and move toward a
source of light with the posterior end facing the light.

DIVISION OF ANIMAL BIOLOGY 89

Diatom Investigations
Paul S. Conger

Preliminary examination was made of about 60 daily plankton samples
and 30 other miscellaneous diatom gatherings, and these were preserved for
further detailed study. The examination indicated that there was com-
paratively little change either in kind or in quantity of diatoms during the
ten-week period, although some species did come in and others dropped out.
It was also evident that there was some slight increase in abundance of
diatoms in the plankton after a heavy wind had stirred up the waters, which
lasted for a period of two to four days after the storm subsided.

Detailed studies were made of the morphology and reproduction of a very
unusual and important new species of Amphora which composed from 20 to
40 per cent of the diatom plankton, and which proved for several reasons to
be quite ideal for such studies.

Single-specimen cultures of a number of species were maintained by a
specially devised method for a period of about six weeks in an attempt to
determine the length of life of these forms, and changes which occur during
aging of the diatoms. Interesting results were obtained but the small num-
ber that time and facilities afforded make this study necessarily preliminary
to further more extensive ones. Another species of Amphora of unique and
characteristic reproduction was carried through several division periods.

Intensive observations and experiments on several diatom species by
hitherto unused methods gave very interesting information relative to the
method of movement in diatoms which it seems to the writer cleared a
number of misunderstandings and definitely furthered our knowledge regard-
ing this old and puzzling question.

Silica analyses were made of several sediments in a study of the diatom-
silica relationships in these highly carbonaceous waters, where silica is very
conspicuously deficient.

Drawings were partially completed and some manuscript written up on
these several phases of diatom research.

The Development and Coordination of Melanophores in Embryos of

pomacentrus

B. R. COONFIELD

This report is concerned with progress made during a preliminary study
of the reaction of the melanophores of Pomacentrus embryos. The embryos
were found attached to the inner surface of unoccupied conch shells. Usually
embryos of any stage of development from the early cleavage stage to the
hatching stage could be found on a single conch shell. These embryos were
removed easily from the shell, since they develop in a capsule, and they were
easily kept in the laboratory.

It was necessary first to observe the appearance of the melanophores in
these embryos. When the embryos reached the twelve-somite stage in de-
velopment two pigment spots appeared in the head region, one on each
side and above the future nares. Soon after this other melanophores ap-

90 CARNEGIE INSTITUTION OF WASHINGTON

peared dorsally in the mid-body region. After this other melanophores
appeared over the body and on the yolk.

The melanophores on the embryo and on the yolk were normally in the
stellate condition. The response of the melanophores on embryos up to the
hatching stage when subjected to various backgrounds was not sufficiently
consistent for the writer to arrive at any definite conclusion as to their co-
ordination. These melanophores, however, contracted immediately in
response to mechanical stimuli. They contracted uniformly also when the
young were subjected to low temperatures. The melanophores in young at
the hatching stage did not respond similarly over the entire body in response
to cold temperature and to mechanical stimulus. By applying pressure on
the head region of the young before the eyes developed these organs were
prevented from developing. Using this method of eliminating the eyes and
also studying melanophore reaction before eyes develop provides a method
of attacking the melanophore response problem in fishes without dealing
with the eye factor. It was observed that the melanophores in developing
embryos without eyes were usually more expanded than those in embryos
with eyes. More experimentation is necessary before any definite conclu-
sions can be drawn as to the coordination of melanophores in the embryos
of Pomacentrus.

Studies of Mangrove and Strand Flora
John H. Davis, Jr.

Besides continuing the investigation of the dispersal, survival, and growth
of the mangroves, particularly Rhizophora mangle, certain studies of the
changes of the strand flora and some analyses of the soils of these islands
were begun.

Rhizophora seedlings marked with different color paints were cast over-
board at four different locations on two trips out from Key West. A signifi-
cant number of these seedlings were recovered washed ashore on the east
side of Loggerhead Key, giving definite data as to the direction and rate of
dispersal. Two groups of seedlings had travelled 18 and 9 miles at the rates
of 0.38 and 0.17 mile an hour respectively. The prevailing easterly winds
and the tide flows probably account for this relatively definite and rapid
dispersion. A few water and air current measurements were made to throw
some light on these molar factors. Although a few thousand seedlings were
cast overboard at 30 and 40 miles, they were not enough, or were not broadly
enough distributed, to float into the Tortugas atoll and be recovered. Col-
lections of other seedlings that normally reach these islands were continued.
All these data seem to show that mangroves are able to migrate great dis-
tances and rather rapidly, and along fairly definite routes.

Over 4400 Rhizophora seedlings were planted on the intertide zone about
Long Key (formerly mistakenly called Bush Key). It is hoped that a
typical red mangrove community will develop from this planting. The good
survival and rapid growth of seedlings planted in 1937 indicates that most
of these will survive. The purpose of these plantings, and probably future
ones, is to see if a mangrove swamp can be started dense enough to hold the

DIVISION OF ANIMAL BIOLOGY 91

present loose coral fragments and calcareous sands, collect more materials
about their roots, and thus build up the reef.

Comparisons of the present flora and the sizes and shapes of the islands
with descriptions by Bowman * and Millspaugh 2 show that there have been
some marked progressive changes on Bush Key and to a less extent on
Loggerhead Key. Some preliminary maps were made to indicate these
changes.

A series of soil studies were begun but results to date are too few for
presentation. The studies of soil salinities show some definite correlations
with the types of plant communities. Further studies of the soils should
prove profitable as soil changes accompanying vegetational changes seem
evident and significant.

Reactions to Light and the Photoreceptors in the Spiny Lobster,

panulirus argus

Walter N. Hess

In common with certain other decapod crustaceans, spiny lobsters from
which the eyes have been removed are sensitive to light. For any given light
intensity, photosensitivity in these animals varies with (a) age of animal,
(6) region of body stimulated, (c) amount of pigmentation, (d) degree of
dark adaptation, (e) general physiological condition of the animal.

Although the dorsal and lateral regions of the abdomen are more sensi-
tive to light than those of the cephalothorax, the degree of photosensitivity
in these regions varies, in general, inversely with the amount of pigment in
the external skeleton. Mature animals with hard external skeletons are
usually sensitive to light only in the regions containing very little or no
pigment, but freshly molted animals are sensitive to light in other regions,
including the antennae, swimmerets, telson, uropods, and the dorsal and
lateral regions of the cephalothorax and abdomen. The degree of photo-
sensitivity is greatest in young animals and in those that have recently
molted. The latter have very little pigment in their external skeletons.

Similar results were obtained in a study of Crangon armillatus. The
freshly molted lobster, Homarus americanus, is also sensitive to light in
many regions of its body.

A study is being made of the neuro-sensory structures in the photosensi-
tive and non-photosensitive regions of these animals.

Habits of the Basket Star (Gorgonocephalus agassizi)
Walter N. Hess and Leonard B. Clark

Observations on the basket star at Tortugas show that it is strictly noc-
turnal. In the evening these animals migrate to the top of coral ledges or,
as is more usual, up the sides of sea fans. Here they spread their branching

1 H. H. M. Bowman, Botanical Ecology of the Dry Tortugas. Carnegie Inst. Wash. Pub.
No. 252, pp. 109-138 (1918).

2 C. F. Millspaugh, Flora of the Sand Keys of Florida. Field Columbian Mus. Pub. No.
118, Bot. Ser. 11, No. 5 (1907).

92 CARNEGIE INSTITUTION OF WASHINGTON

arms, which serve as a net for capturing food. As daylight approaches they
withdraw their arms and retreat to shaded regions.

These animals can best be collected at night by the use of flashlights or
submerged lamps. If nets are used, the animals are usually injured in
removing them from their attachment, but if the sea fans to which they are
attached are also taken they can be collected uninjured.

Contrary to the general impression, basket stars are quite common on
coral reefs especially where sea fans occur.

Studies on Tumors in Cold-blooded Vertebrates
Balduin Lucke

The comparative study of neoplastic growths has in the past dealt chiefly
with tumors in mammals and birds, neglecting the more primitive cold-
blooded vertebrates. This restriction has been due largely to the belief
that among amphibians, reptiles, and fish, neoplasms are rare and difficult to
obtain for study. Information concerning tumors in these classes has been
based upon chance observations, rather than upon systematic investigations
of particular kinds of tumors in certain species. It seems not unlikely,
however, that such study would add much to our knowledge concerning the
nature of neoplastic growths in general.

The aim of the present work was to investigate the occurrence, distribu-
tion, and nature of tumors among the fish and turtles available in the waters
around the Dry Tortugas. The search has yielded much additional infor-
mation about tumors of nerves in fish of the snapper family (the first ac-
count of which was given in last year's report) ; in addition, two new varie-
ties of tumors were found, one in the green turtle, another in the slippery
dick, a small reef fish. These several kinds of tumors are common and
occur in easily available species, and all of them appear to be suitable for
a more detailed experimental investigation.

Nerve sheath tumors (neurilemmoma, neurofibroma, schwannoma) in fish
of the snapper family (Lutianidce) . This investigation is a continuation of
the study reported in the Year Book for 1936-1937. The total number of
tumors which have been obtained to the present is 76. This relatively large
number permits a more precise analysis of the anatomical distribution and
habits of the growths. It is found that most of the tumors are situated
along the course of the larger subcutaneous nerves, particularly those of the
head and the dorsal regions. Their peculiar distribution, together with their
characteristic histological appearance, now makes it very probable that these
growths have their origin in the sheath of the nerves. They bear a striking
similarity to tumors of the nerve sheath in man. Like them they form two
main types, in one of which the component cells are oriented in such a manner
as to form rows or so-called palisades; the other type has a very loose
edematous structure, and no particular arrangement of its component cells
is demonstrable. It is estimated that approximately 1 per cent of gray
snappers (Lutianus griseus) are affected with this neoplasm; the incidence
in the other varieties of snappers is not known.

DIVISION OF ANIMAL BIOLOGY 93

Transplantation experiments were made using a technique which had
proved successful with an amphibian tumor studied by the writer. Small
fragments were inoculated by means of a hollow needle into the anterior
chamber or the vitreus of the eyes of a number of snappers. After from 8
to 10 weeks the inoculated fish were killed and the eyes excised and prepared
for histological examination. The results of these transplantation experi-
ments will be reported on completion of the study.

Multiple papillomas of the skin and the eye in the green turtle (Chelonia
my das). The newgrowths which have been observed in reptiles are even
more limited in number than is the case in amphibians and fish. Hence it
is of particular interest to record that green turtles not infrequently suffer
from papillomatous neoplasms which may attain so great a size as seriously
to interfere with their locomotion.

The tumors occurred in a large female green turtle caught off Cape Sable.
They were located on the edges of both anterior flippers, in the axillary re-
gions, the neck, on the eyelids, the corneal surfaces, and on the tail. In shape
they were hemispherical or globular, and had rough, warty surfaces covered
with dry, coarse, cornified epiderm, which in some areas was superficially
ulcerated. Some of the tumors were sessile, others had a broad pedunculated
base. In some areas, particularly in the axillary regions, several were
crowded together, elsewhere they were solitary. In size, the individual
tumors ranged from small warts a few millimeters in greatest diameter to
large masses nearly 5 cm. in diameter. All were of tough consistency, and
had a dense white fibrous, bloodless cut surface.

Histologically, the neoplasms are typical papillomas, consisting of a fibrous
core covered with many layers of epiderm the surface of which has under-
gone extensive keratinization. All stages of the papillomatous growth are
represented in the animal; the smaller show a relative preponderance of
epithelial over mesodermal components; as the tumors increase in size the
fibrous components become more prominent, in the largest growths they
greatly predominate. Richly cellular areas, frequently encountered, indicate
that the fibrous portions of the tumors are actively proliferating.

The papillomas of the turtle correspond very closely to epidermal papil-
lomas of man and other mammals. Several of these have been shown to be
caused by viruses. It would be of great interest if a similar etiologic factor
could be demonstrated in these papillomas of a very different group of
animals.

Epithelial growths of the skin in the slippery dick (Halichoeres radiatus).
There is no sharp dividing line between "true" neoplasms and certain ex-
aggerated growths due to irritations of one kind or other. Indeed many
of the latter have been found to merge by ill-defined stages with the former.
Their study is the more indicated because the transition stages may furnish
information as to the nature of neoplastic growths in general. A tumorous
condition which seems to belong in this border-line group occurs as a rather
common disease in the little reef fish, slippery dick. Thirty examples were
observed among approximately 6000 of these fish. The tumors generally are
circumscribed, flat, somewhat nodular elevations of the skin tending to
undergo ulceration. They have a grayish, dull appearance and a soft con-

94 CARNEGIE INSTITUTION OF WASHINGTON

sistency. The scales in affected areas are elevated or have apparently been
destroyed entirely. The disease is distributed over many parts of the sur-
face, but is most commonly encountered in the caudal region; destruction
of fins is common. The growths often attain very large size. Histologically
they are composed of masses of epidermal cells, arranged in alveolar group-
ings; stroma and vessels are scanty. The corium is infiltrated but no ex-
tension into the subjacent musculature is observed in the present series. In
many tumors striking cytological changes have taken place; the cytoplasm
is ballooned and partly occupied by a small deep staining chromatic body
surrounded by faintly acidophilic material ; the nature of these inclusions is
still a matter of uncertainty.

Fish affected with these tumors can readily be kept in indoor aquaria.
They should prove excellent material for the experimental investigation of
this disease.

Further Studies on the Electrical Behavior of Valonia ventricosa

Gordon Marsh

By means of a rotating sector disk giving two equal light-dark periods per
revolution, intermittent and continuous light were compared in their effect
upon the inherent E.M.F. of Valonia. At frequencies of about 8 to 10 per
second and intensities up to 1600 foot-candles no consistent difference was
found, the effect of intermittent light approximating that of continuous light
of half the intensity.

The effect of KCN upon the potential was determined over the range of
concentrations from 2 X 10— 8M to 5 X 10~3 both in light and in darkness.
The cyanide was dissolved in sea water and the latter restored to its original
pH with HC1, using thymol blue as indicator. When the steady potential in
the presence of cyanide is plotted against concentration, a curve results
which drops rapidly to around 1 X 10~~ 4M and but slightly more for higher
concentrations. All depressions in potential were reversible during the time
limits involved. Recovery of the original potential upon removal to sea
was slower the higher the concentration of cyanide used. In the dark the
maximum depression obtained varied from 40 to 75 per cent. In the light
the depression was much greater both as a percentage and as an absolute
figure ; the potential level in high concentration of KCN was approximately
the same in light as in darkness. This is consistent with the known effects
of cyanide, which normally depresses respiration reversibly to the above
amounts for many materials and at high concentrations completely inhibits
photosynthesis. NaCN yielded substantially the same results as KCN.

A similar study was made with ether between the concentrations 0.01 and
2.5 per cent by volume. The curve of potential vs. concentration resembles
roughly that obtained with cyanide. Reversible depression of the potential
was obtained with concentrations up to 1.0 per cent; 1.5 per cent and higher
coagulated the protoplast. The individual variability of behavior of the
cells was high, as is typical of the effect of ether. Concentrations between
0.5 and 0.1 per cent produced a preliminary increase in potential which in
extreme cases reached eight times the value of the potential in sea water

DIVISION OF ANIMAL BIOLOGY 95

for cells in the dark and three times the value for cells exposed to light, and
required about three hours to descend to a steady level.

A preliminary survey of the influence of the pH of the surrounding sea
water on the protoplasmic potential difference was made, using sulfon-
phthalein indicators. The potential increased with pH 4 — 11, the effect of
equal pH steps being less near the pH of sea water. Differences were ob-
served between the effects of KOH and NaOH and between the effects of
illumination at low and at high pH's.

The Response of Ascidian Larvae Toward Certain Hormones

Paul A. Nicoll

The immediate stimulus of ascidian metamorphosis, regardless of the ulti-
mate cause, may be regarded as a state of condition incompatible with con-
tinuance of larval life. The subsequent differentiation, development, and
growth of the primitive cells from which the adult organism arises follows
this breakdown of the larval action system more or less rapidly depending
on the species under consideration. Grave and Nicoll (in press) have sug-
gested several paths by which this condition could be reached. This summer
a start was made in the study of possible factors which would prevent the
development of this state of condition that terminates larval existence and
so permit the more highly organized prochordate type of individual to survive.

The possibility of a deficiency or complete lack of some hormone essential
for completion and survival of the prochordate animal was investigated.
Using the same technical procedures described by Grave, larvae of Ascidia
nigra were subjected to various concentrations of theelin, theelol, adrenalin,
thyroxine, and testosterone, as well as a cortical extract of proved potency for
survival of adrenalectomized dogs. The first three hormones were supplied
through the kindness of Parke, Davis and Company. Of these only theelol
and adrenalin had any influence on the larvae, which in both cases amounted
to lengthening the larval life period but without allowing any development
of a digestive or circulatory system, which would seem to be necessary if
the prochordate type were to have a separate existence. Technical difficul-
ties prevented adequate tests with testosterone but the failure of crystalline
thyroxine to influence metamorphosis in either direction was definite.

In addition to the hormone experiments the larvae were treated with two
crystalline vitamins, vitamin C and vitamin B1? on the theory that possible
deficiencies of basic food essentials might lead to the breakdown of the larval
action system. However, neither of the vitamins, using a wide range of con-
centrations in both cases, was found to influence in any way the length of
larval life.

Besides the experimental work considerable time was devoted to the collec-
tion and study of various species of ascidians that may be found in the waters
near the Tortugas Laboratory. Two regions previously uninvestigated which
proved rich in ascidians of all species were located on the east sides of Sand
and East Keys.

Of the many species collected, some of which will undoubtedly prove to
be undescribed when thoroughly studied, one may be mentioned at this time.

96 CARNEGIE INSTITUTION OF WASHINGTON

It is a member of the genus Ascidia and appears more closely related to
Ascidia hygomiana than to others of the group. It differs markedly from
other species of the genus in three important aspects: (1) The dorsal tubercle
is much larger and though heart-shaped is very decidedly convoluted even
in young specimens. (2) The eggs are two to three times the size of the
other species of Ascidia found in the region, and the outer test cells are deeply
pigmented, giving the eggs a brownish color in place of the milk-white color
found in other species. (3) The adults, which range in size up to 90 by 35
mm. and are quite thick owing to a large mud sack, have a thin test that is
almost colorless. They may range in color, however, from brilliant red
through orange-brown to gray or colorless owing to pigment in the mantle
cells. Although insufficiently studied at this time to insure its acceptance
as a new species, it has been given the tentative name of Ascidia gardenensis.
The name is derived from Garden Key, where the first individuals were col-
lected, though later specimens were found at East Key.

Studies on the Development of Ptychodera Bahamensis

Fernandus Payne

Three things were attempted during the summer of 1938. Ptychodera
bahamensis is supposedly a protochordate. If so, what would be the effects
of the anterior pituitary hormones on the development and discharge of the
sex cells? Without giving details of the experiments, the answer is that no
effects were observed. Five years earlier when fertilization and larval de-
velopment were studied, transformation was not obtained. A second attempt
was made the past summer, but for some unknown reason the larvae after a
week or ten days remain about stationary. With the idea that thyroxine
might hasten transformation, larvae were subjected to a sea-water solution
of thyroxine (1 g. to 1000 cc.) for 24 hours. No effects were noticeable. It
was not even toxic, while whole thyroid solutions were toxic. Larvae lived
in the laboratory for 25 days. No larvae were taken in the tow although such
collections were examined every day for five weeks. The sand in the imme-
diate vicinity of the adult forms was examined carefully with the eye and
also with the aid of a low-power binocular microscope, but no recently trans-
formed individuals were found. The smallest specimens discovered were
about 1 inch in length. Six weeks seem too short a period to unravel this
story.

For some time the writer has been interested in the cytology of secretion,
and since the body wall of Ptychodera contains many large and different
kinds of secretory cells, material was collected for later study.

On July 24, Amphioxus larvae were discovered in tow taken on the west
side of the island between the lighthouse and the south end. Continued
daily observations were made up to and including August 4. Larvae were
present each day during this period. Adults, of course, are present some-
where in this vicinity, and if they can be discovered will prove useful material
for further investigations. Many of the larvae were fixed for cytological
studies.

DIVISION OF ANIMAL BIOLOGY 97

Investigations on Ascidians
Harold H. Plough and Norms Jones

The entire season was devoted to the study of the structure, development,
budding, and colony formation of Ecteinascidia tortugensis sp. nov. mentioned
in our previous reports in Year Books for 1935-1936 and 1936-1937. The
stolons of this species have been used in all our composite colonies and
chimaeras with E. conklini and Perophora, so that it seemed desirable that a
complete morphological description of this species should be available previ-
ous to any account of the experimentally produced specimens. As soon as a
few final drawings are added to the plates this account will be ready for
publication, for the study is now in manuscript.

During the 1938 season E. tortugensis was one of the commonest ascidians
at the Tortugas. That it has not been studied before seems to be due to its
rather small size (5 to 6 mm.) and its relatively inaccessible habitat. It was
found occasionally on the under sides of rocks under the coal wharf at Garden
Key, but during late July and early August it occurred in large numbers on
the under sides of rocks just below low-water mark on the outside of both
Bush Key and Long Key. Later it was found in similar situations on Bird
Key Bank and (by Dr. Nicoll) at East Key. It appears to prefer these
exposed locations where there is constant wave action and consequently pure,
relatively cool water.

One or two morphological facts are worthy of note here: (1) The oviduct
in Ecteinascidia was observed first by Berrill x (E. turbinata and E. conklini) .
It was found in E. tortugensis in the same situation, namely a short wide
straight tube, through which eggs pass directly from the ovary to the pos-
terior (aboral) end of the right atrial cavity. The latter is the brood pouch
in which the eggs develop to the larval stage. (2) Soon after the tadpole
larva is expelled from the atrial siphon, the stigmata become visible though
not yet functional. Four rows of stigmata are clearly present at this stage,
and this observation has been confirmed by examination on mounted speci-
mens. Since this does not agree with Berrill's 2 account of E. conklini, we
examined larvae of the latter. In these too, four rows are clearly visible in
the earliest stages. Thus these Ecteinascidia correspond more closely than
Berrill supposed to the larvae of Ascidiidae and Styelidae. (3) E. tortugensis
is always closely attached to the rock by the test along its ventral side below
the endostyle. In this it is quite unlike the other Ecteinascidia and Pero-
phora, which are attached by stolons at the posterior end. In this mode of
attachment it closely resembles many of the solitary species of Ascidia.

The relationships of the family Perophoridae (to which Perophora and
Ecteinascidia belong) are still in question. Van Name 3 has included them
with the Ascidiidae, while Berrill 4 considers that they are distinct and offers

XN. J. Berrill, Ascidians of the Bermudas. Biol. Bull., vol. 62 (1932).

2N. J. Berrill, Studies in tunicate development III. Phil. Trans. Roy. Soc. London,
ser. B, No. 226 (1935).

3W. G. Van Name, Ascidians of the West Indian region. Bull. Amer. Mus. Nat. Hist.
No. 44 (1921).

* N. J. Berrill, Studies in tunicate development V. Phil. Trans. Roy. Soc. London,
ser. B, No. 530 (1936).

98 CARNEGIE INSTITUTION OF WASHINGTON

several suggestions as to their derivation. In general the study of this new
species appears to lend weight to one of Ben-ill's three alternatives,5 that
they represent "an early step in the change from a cionid to an ascidiid type."

Study of the Plankton in Tropical Waters
Gordon A. Riley

The small quantity of plankton in tropical waters, as contrasted with that
in higher latitudes, provides an interesting study of the differential effect of
environmental factors. The work reported here is intended as a preliminary
survey of the problems involved. In the final report a study of Long Island
Sound will be included for comparison.

The mean quantity of chlorophyll and total plant pigments in fifteen series
of samples was found to be approximately one twenty-fifth the amount in
Long Island Sound. The plant pigments in the net plankton averaged 1 per
cent of spring bloom conditions in the Plymouth Sound region, described by
Harvey, Cooper, Lebour, and Russell in 1935. The ratio of plants to animals
is about the same in both regions.

The amount of soluble phosphate was small, averaging 1.3 mg. of P per ms.
Analyses of nitrate were not made, but experiments show that it, rather than
phosphate or iron, is the most important limiting factor.

In order to estimate productivity, light and dark bottles containing ordi-
nary sea water were suspended at various depths and after a period of five
to seven days were analyzed for oxygen and occasionally for chlorophyll
and P. The oxygen production averaged 0.96 mg. per liter per week at a
depth of 1 m. This is one-third to one-half the amount produced in Long
Island Sound. It would therefore appear that the actual productivity is
much greater than the standing crop would indicate. This tends to support
the theoretical considerations discussed by Harvey and his associates in
1935. It should be added, however, that the photosynthetic rate is not an
absolute index of productivity. The values obtained at these high tempera-
tures (27.5 to 29.0° C.) must be discounted by experimental means in order
to allow for the higher metabolic rate. Until then, an accurate comparison
cannot be made.

The productivity equation is

W = 2.18* + 0.75i/ - 0.00035^ - 0.09

where W is oxygen production in grams per m3 per week, x is chlorophyll in
milligrams per m3, y is P in milligrams per m3, and 2 is the number of ani-
mals per m3. The correlation between calculated and actual values for
oxygen production is 0.706. According to the equation, animal consumption
is an important factor, causing 35 per cent of the variations in oxygen pro-
duction. Contrary to the experimental evidence, phosphate appears to be
responsible for 38 per cent of the variations. It is possible, however, that
the constant is weighted by a direct relationship between variations of nitrate
and phosphate.

*IMd.,v- 60.

DIVISION OF ANIMAL BIOLOGY 99

Regeneration in the Starfish Linckia and in the Protozoan

condylostoma

Vance Tartar

Regeneration in the starfish Linckia. The starfish Linckia is remarkable
in being able to regenerate the whole animal from a single isolated arm with-
out any part of the original disc. It was proposed to find out what regenera-
tion would occur in isolated arms having a cut surface at each end, in the
hope of identifying the factors which determine whether a disc or an arm
tip will be formed at a cut surface. Arms of Linckia were cut off near their
bases and the tips likewise removed so that the fragments had a cut surface
at each end. Since the arm tapers very little, the two wound areas were
approximately equal in size. In order to distinguish the proximal from the
distal end, the latter was always cut at an angle to the axis of the arm, a
procedure which tended to equalize the area of the two cut surfaces. Re-
generation at both ends of such fragments was compared with that of isolated
arms having only one cut surface and with that of discs from which the arms
had been removed. A total of 142 isolated arms, together with 46 discs,
comprised the material for this study. The results of the study are as
follows :

1. Regeneration was most rapid in armless discs, and slowest in whole
stars with only one or two arm tips removed.

2. In five cases regeneration at the cut surfaces on the original disc was
more rapid than that on the proximal (same level) cut surface of arms
isolated from that disc. In only one case was this relationship reversed,
with a slightly more rapid regeneration in the isolated arms.

3. Seventeen armless discs showed equal regeneration on all cut surfaces,
while in twelve cases the regeneration was not uniform.

4. The rate of regeneration in isolated arms is, within wide limits, not
correlated with the size of the fragment.

5. There was no demonstrable difference in the rate of regeneration in
isolated arms having one, as compared with those having two cut surfaces.

The above two facts suggest that the materials for regeneration are sup-
plied only by the tissues adjacent to the cut surface.

6. When the, fragments are sorted into three size groups, an interest-
ing relationship is shown. Of 15 large isolated arms of length 64-48 mm.,
3 regenerated into 5-armed starfish, and 12 into 6-armed stars. Of 35
medium-sized fragments of length 45-31 mm., 3 regenerated into 4-armed,
19 into 5-armed, and 13 into 6-armed starfish. Of 26 small fragments of
length 29-14 mm., one regenerated into a 4-armed, 21 into 5-armed, and 4
into 6-armed stars. It is suggested that the number of arms differentiated
from the blastema depends to some extent upon the size of the fragment, the
smaller fragments tending to have fewer arms than the larger. A sample
of 60 starfish collected at random consisted of 33 stars with 5 arms, 26 with
6 arms, and one with 7 arms.

7. Under normal conditions polarity is maintained in the isolated arm,
that is, the proximal end regenerates the disc and the distal end an arm tip.

100 CARNEGIE INSTITUTION OF WASHINGTON

8. Regeneration at the proximal cut end of an isolated arm was generally-
more rapid than at the distal cut end. Twenty-three cases showed more
rapid regeneration proximally than distally, and in only six cases did the
regeneration appear to be approximately equal at both ends. The remain-
ing fragments showed no regeneration at the end of one month.

9. In one isolated arm regeneration failed to occur at the proximal cut
surface, but an arm tip was formed at the distal surface.

These data clearly show that under normal circumstances the polarity
of arms is not altered by isolation, but a remarkable specimen of Linckia
found by Dr. H. H. Darby at Tortugas some years ago suggests that
under certain conditions loss of polarity may occur. This was a double
animal which had two small discs of slightly unequal size connected by a
large arm. The most reasonable explanation of the origin of this animal
is that it was formed by an isolated arm which regenerated a disc at both
ends.

Specimens of the starfish were preserved for species identification. The
writer takes pleasure in expressing his indebtedness to Dr. Hugh H. Darby
for his interest in this problem and for his helpful suggestions during the
course of the work.

Regeneration in the ciliate Condylo stoma. In the large brackish-water
ciliate Condylostoma (probably magnum) the macronucleus is clearly visible
in the living organism as a string of nuclear beads, all contained within the
same membrane, which extends along the right side of the elongate cell. The
distribution of the macronucleus in the trophic stage is such that if the cell
is cut in two longitudinally, the right half (which will be referred to as the
A-fragment) contains two to three times as many nuclear segments as the
left half (B-fragment), in which their number is usually 5 or 6. Apart from
this difference in quantity of nuclear material the two halves were equivalent,
each being of the same shape and size, and containing equal portions of the
cytoplasmic differentiations of the original cell. It appeared therefore that
this protozoan offers the peculiar opportunity of obtaining two half-frag-
ments which are equivalent in all respects except that one contains two to
three times as much nuclear material as the other; and it was proposed to
follow the fate of these fragments to determine the influence of the amount
of nuclear material on the rate of regeneration.

For the purpose of the present problem it was necessary that the two
fragments to be compared both lived, regenerated, were of equal size, and
maintained the elongate shape after cutting. Out of over 100 sets of such
fragments, only 10 fulfilled all these requirements, and these 20 fragments
form the material from which the following results were obtained.

1. In one case the two fragments regenerated in the same time, while in
all other cases the fragment containing more nuclear material regenerated
more rapidly than its partner with less nuclear substance. The average time
for regeneration of A-fragments was 20.3 hours, while B -fragments required
41.2 hours.

2. It is not to be concluded, however, that the differentiation process itself
proceeded at different rates in the two series ; for when the time for regenera-
tion is measured, not from the instant of cutting, but from the time of the

DIVISION OF ANIMAL BIOLOGY 101

first appearance of the anlagen of the cell differentiations, the two series are
approximately equal. The average time for the visible differentiation pro-
cess in A-fragments was 18.0 hours, as compared with 18.9 hours for B-frag-
ments.

3. The condition of the macronucleus in 8 of the 10 B-fragments was
determined at the time of completion of regeneration. These fragments had
all regenerated the nucleus, i.e., instead of only 5 or 6 nuclear segments
located in the anterior end as at the time of cutting, there was a long chain
nucleus extending the length of the cell.

It may be suggested simply as a tentative hypothesis that the additional
time required for most of the fragments with fewer nuclei to regenerate was
due, not to a retardation of the differentiation process itself, but rather to
growth of the nucleus which is necessary before the cytoplasmic regenera-
tion can begin.

As stated above, it was rarely that the longitudinal half-fragments with
only 5 to 6 nuclear segments remained elongate, and in this respect they
differed markedly from the companion fragments with two to three times
as much nuclear material. Thus it was common for the fragments to con-
tract into a modified spherical form, from which they seldom recovered.
Of 66 A-fragments in the trophic stage, 60 remained elongate, while only 6
contracted into a ball. These halves are to be compared with 54 B-frag-
ments, also in the trophic stage, of which only 15 remained elongate, while
39 assumed the spherical shape. Thus a diminution of the amount of nuclear
material favors the assumption of a form with minimum surface.

In division the protozoan elongates by stretching, the cytoplasm becomes
darker and more granular, the macronucleus contracts into a short rod lo-
cated near the mid-point of the cell, and the anlagen of the new pharynges
of the daughter cells appear, one at the anterior end, and the other at the
middle of the cell. Two such dividing Condylo stoma were cut transversely
so that in one case the macronucleus remained entirely within the anterior
daughter cell, while in the other the nucleus was confined to the posterior
partner. (The fate of the micronuclei was undetermined, though it is prob-
able that they remained closely associated with the macronucleus.) In both
cases the cytoplasmic differentiation stopped immediately in the enucleate
cell, but went to completion in the nucleate half. Thus the presence of the
macronucleus is apparently required throughout the process of differentiation.

In two cases the cells were split longitudinally, but the two equal halves
remained connected by their posterior ends. Such cells stretched out into
elongate bands of which the half with the greater number of nuclear beads
formed the functional anterior end. Regeneration of the couplet was ac-
complished by division. The anlage for the pharynx of the anterior daughter
appeared at the anterior end of the A-fragment, while that of the B-fragment
appeared at the point of connection, i.e., at its posterior extremity. Thus the
polarity of the B-fragments became completely reversed.

Several hundred normal Condylostoma from the stock culture were ex-
amined and none of these departed from the following description: On the
ventral side at the anterior end is the large groove-like pharynx, having a
prominent membranelle and mouth on the right side and a row of large ciliary

102 CARNEGIE INSTITUTION OF WASHINGTON

plates on the left. In contrast to this uniformity, the regeneration of frag-
ments frequently produced atypical forms of great variety. Abnormality
was most frequent in B-fragments, which began with a very low nucleo-
plasm^ ratio. The distribution of abnormal forms was as follows:

Of 66 A-fragments, 60 were normal and only 6 abnormal.

Of 47 B-fragments, only 9 were normal, while 38 were abnormal. These
classes contain the following subclasses, which indicate that abnormality of
the regeneration was not necessarily connected with the irregular (spherical)
shape which the fragments so frequently assumed.

Of 6 spherical A-fragments, all were normal.

Of 60 elongate A-fragments, 6 were abnormal.

Of 34 spherical B-fragments, 29 were abnormal.

Of 13 elongate B-fragments, 9 were abnormal.

Space does not permit a complete description of all abnormalities en-
countered, but several types may be enumerated: (1) reversed pharynx, pro-
ducing an animal which was the mirror image of the normal (7 cases) ;
(2) circular pharynx, in which the membranelle and the row of ciliary plates
formed more or less complete concentric rings (32 cases) ; (3) double pharynx,
several types (13 cases) ; (4) double animal, having two pharynges and two
"tails" oppositely directed (1 case) ; (5) heteromorph, having a pharynx at
each end of the cell (2 cases) ; (6) pharynx open at each end (2 cases).

During the life of such abnormal cells there occurred frequent dedifferen-
tiation and redifferentiation so that the pharynx changed from one form to
another or even attained the normal form in some cases. It was demon-
strated, therefore, that in regeneration of Condylostoma the normal form
and typical arrangement of cytoplasmic differentiations may easily be altered.

The Effect of Intensity of Light on Photodynamic Reactions

D. H. Tennent

This work was in continuation of that reported in Year Books Nos. 34,
35, and 36. A General Electric exposure meter, with calibrated filters, was
used to determine the intensity of sunlight, or of artificial light, used in
irradiating Lytechinus eggs in solutions of dye in sea water.

Each lot of eggs was divided into portions and the different portions
irradiated with light of full intensity or, by the introduction of calibrated
filters between the source of illumination and the eggs, with light of reduced
intensity. Opal glass plates, Whatman's filter paper no. 50, and various
Corning glass filters were used in reducing the intensity and changing the
quality of light reaching the eggs. The greater part of the work was done
with Greubler's neutral red in 1:150,000 sea-water solution, and a smaller
amount with National Aniline Company's brilliant cresyl blue and Coleman
and Bell's brilliant green.

In the experiments performed, uninseminated Lytechinus eggs in 1:150,000
solution of neutral red in sea water were irradiated with sunlight or with
artificial light at intensities varying from 25 to about 14,000 foot-candles.
After irradiation the eggs were inseminated and studied carefully under the

DIVISION OF ANIMAL BIOLOGY 103

microscope for surface changes, formation of fertilization membrane, cleav-
age, etc.

The analyses of the data completed at the present time indicate that the
threshold for violent surface reaction (blister cytolysis) of Lytechinus eggs
in neutral red sea water lies at about 2500 foot-candles. At an intensity of
250 foot-candles the eggs did not blister and cleavage did not go beyond the
8-cell stage; at 500 foot-candles there was no blistering and little normal
cleavage ; at 2100 foot-candles, no blistering and no normal cleavage beyond
the 8-cell stage. At intensities from 3000 up to 14,000 foot-candles there
was a regular increase in the violence of the surface reaction and complete
inhibition of the cleavage processes.

GEOPHYSICAL LABORATORY l

L. H. Adams, Director

To the geologist differentiation means the process by which a molten
silicate mass produces rocks of different kinds. But the term differentiation
has a far wider significance, and properly may be applied to any change
from a simple state to a complex one. Opposed to differentiation is assimi-
lation, which means the incorporation of one rock mass by another, or, more
generally, a change in the direction of uniformity or simplicity. We recog-
nize differentiation and assimilation as the agents that, operating throughout
all geologic time, have caused the Earth to attain its present condition.
Indeed all changes in the physical world may be thought of as consequences
of these two processes. It is instructive also to regard differentiation merely
as a decrease of entropy, and assimilation an increase in the same somewhat
mysterious quantity, which is used in exact statement concerning change
because it allows us to describe change in terms of definite and unambiguous
units.

Perhaps the greatest generalization in the physical sciences states that the
entropy always tends to increase in the course of any spontaneous process
unless special forces or restraints are imposed on the system under considera-
tion. The famous generalization teaches us that the natural and universal
tendency is assimilation. Left to themselves, all aggregations of matter tend
to become uniform throughout; the ultimate state, if no hitherto undis-
covered factors intervene, is one of complete homogeneity. Diffusion, a
manifestation of the ceaseless motion of atoms and molecules, would in time
reduce the Earth and the whole universe to a state in which the composition
of any cubic centimeter of space would be exactly the same as that of every
other cubic centimeter.

The significant fact is that the primary tendency for all aggregations of
matter is a degradation of form, of energy, or of. composition. Mountain
masses are reduced to peneplanes, thermal energy becomes unavailable for
useful work, and mixtures become homogeneous in composition and texture.
But although the tendency is ever toward the state in which individuality
is destroyed, there are intermediate stages in which the natural and usual
course of events reverses itself; we have alternate cycles of the twin effects
that, depending on the factors to be emphasized, may be designated as
mixing and unmixing, planation and upheaval, diffusion and segregation,
destruction and creation, decay and growth, or assimilation and differentia-
tion— different names for the one set of fundamental opposing tendencies.

Viewed in a broad way, the problems of geophysics are largely those of
differentiation. Whether all or a part of the Earth was once uniform in
composition, it is now decidedly heterogeneous, and differentiation is respon-
sible for those aspects of its geologic history that are the most interesting
and also the most puzzling. It is easy to understand how materials can mix
to form a solution, but it is difficult to acquire adequate knowledge concern-
ing the mechanism by which they can unmix. A land surface by well-known
processes is reduced to a level plane, and subsequently by forces that are not
yet well understood is uplifted to great heights. There is a general tendency

1 Situated in Washington, District of Columbia.

105

106 CARNEGIE INSTITUTION OF WASHINGTON

to reduce the state of all things to a dead level, and the consequences of this
tendency are simple. The reverse effect of building up structures and differ-
ences in composition is complex and often appears to defy explanation. In
many instances we can predict the course of processes by which structures
are torn down but not the manner in which they may be built up again.

That part of the Earth's crust amenable to direct or indirect observation
offers a fascinating series of problems, which in common with all problems
present a challenge to the inquiring mind. In accepting the challenge we
resort to laboratory experimentation and in effect presume to imitate Nature
on a small scale. At the Geophysical Laboratory our attack has proceeded
in three principal directions: (1) By crystallization or by other means, we
induce the separation of mixtures into their constituents (solid, liquid, and
gaseous) and define the conditions necessary for the appearance of the
individual phases; (2) we search for mechanical processes that will sort,
transport, and arrange the products, and (3) wTe study the structure of solids
and liquids, utilizing the most powerful devices of modern physics, in order
to predict the behavior of mixtures subjected to varying environment.

During the past year important progress has been made in each of these
major lines of attack. A lengthy investigation of the volatile constituents
of natural rocks and a comparison with the gases that, emanating from
volcanoes often in tremendous volume, contribute to their awe-inspiring
eruptions has established striking similarities in composition and has thrown
light on the properties of lavas, on the phenomenon of volcanism, and on
the mechanism of flowage in masses of molten silicates. Studies of the
incrustations from volcanoes and fumaroles have shown the presence of a
surprising number of the less familiar elements and have suggested that the
deposition of these elements in considerable amount by volatile transport is
an important factor in one variety of differentiation, the formation of ore
deposits. Closely related to the work of the Geophysical Laboratory, and
in effect a part of its program, is the thorough investigation of volcanic
phenomena at Montserrat carried out by F. A. Perret, a Research Associate
of the Institution. The results of a study extending over a period of four
years have been assembled for publication as a companion volume to the
previous memoirs on Vesuvius and on Mont Pelee by the same investigator.

Several systems containing water as an active ingredient have been
successfully investigated. Among these are: boron oxide and water, which
shows up some of the conditions under which difficultly crystallizable sub-
stances make their appearance ; calcium sulfate and water, which has cleared
up some puzzling questions concerning the formation of gypsum deposits;
and sodium hydroxide and water, the study of which marks the first step
in one program for the thorough investigations of silicate systems at
moderate temperatures and pressures — a program made feasible through
financial aid by the Carnegie Corporation of New York and having as its
objective the acquiring of knowledge concerning the formation of pegmatites
and the hydrothermal alteration of minerals. In a systematic study of the
constitution of samples of the ocean floor collected by the Carnegie numerous
minerals have been identified and found to include dolomite, which obviously
was deposited directly from the sea water. Further studies of the constitu-

GEOPHYSICAL LABORATORY 107

ents of deep-sea samples will be greatly facilitated by the portable winch
which has been constructed and made ready for collecting cores from the
bottom of the oceans at their greatest depths.

Directly applicable to many great problems of differentiation are the
results of recently completed investigations on the melting behavior of
various combinations of rock-forming oxides; somewhat less directly appli-
cable but quite essential are other researches of the past year, notably the
study of the properties of solutions under pressure and the measurement of
latent heats of fusion by a rapid and convenient method.

The principal features of recent and current investigations at the Geo-
physical Laboratory may be summarized as follows.

THE VOLATILE CONSTITUENTS OF MAGMAS

Gases in rocks. In the course of our first investigations of volcanoes it
became evident that further information concerning the nature and com-
position of volcanic gases was essential. The study of these gases naturally
led to an investigation of the small but significant amounts of gases that
are found in practically all types of rocks. By suitable treatment, such as
heating the rock samples under reduced pressure, the gases can be extracted
from the rocks and collected in quantities sufficient for chemical analysis.
A comprehensive series of investigations [Shepherd] on the volatile con-
stituents of lavas and various plutonic rocks has now yielded information
that throws light not only upon the phenomenon of volcanism but also
upon the mechanism by which some geologic formations are produced.

Results obtained for the vacuum-tube samples collected at Kilauea —
the only volcano from which it has been possible to secure entirely satis-
factory gas samples — demonstrated that the composition of the gas expelled
from a volcano is not constant. The most outstanding characteristic is the
preponderance of water, which comprises eighty per cent or more of the
total volume of these gases. The lack of uniformity in the gases from
Kilauea is readily explained by the nature of the volcano structure. A
process of local concentration is believed to be responsible for the varying
composition of not only volcano gases but also those obtained by exhausting
rocks in vacuo. These processes of local concentration and re-volatilization
have far-reaching significance for both volcanology and petrology.

Following the study of volcano gases the next step was the determination
of the gases retained by freshly collected lavas. Comparison of these
measurements with the data for vacuum-tube samples showed the composi-
tion to be sensibly identical and warranted the inference that similar studies
of lavas from craters that are not suitable for direct gas-collecting should
furnish useful information concerning the gases erupted at such sources.
Analyses of the gases from lavas of Mont Pelee, Martinique, and of Lassen
Peak, California, were made. Just as was the case for volcanic gases, the
results showed that the composition is variable and that water is the
dominant constituent. Fluorine appears as a more common element than
had been expected, the hydrocarbons are practically absent, and the rare
gases are present only in minute amounts.

108 CARNEGIE INSTITUTION OF WASHINGTON

Other measurements were made on a number of typical rocks, such as
obsidians, granites, and diabases. Of much interest is the conclusion that
the volumes of gas retained by lavas and plutonic rocks tend to cluster
around a series of values that are characteristic of the rock type. Thus
with lavas, about 6 cubic centimeters per gram of rock is the usual amount,
for both andesitic and basaltic lavas. When exceptions occur they usually
can be connected with features revealed by a careful examination of the
material. Presumably the above figure is related in some way to the
solubility or vapor pressure of the volatile constituents in the silicate magma,
and to the temperature and pressure at the time of extrusion.

On the other hand, the volume of gases obtained from the plutonic rocks
is usually about 30 cc/g. For granites this figure is in accord with what
would be expected if we take account of the mica and hornblende and allow
a little for adsorbed water, but it should be noted that diabase yields nearly
the same amount of gas. This value, 30 cc/g, represents a minimum for
these rocks, and is increased many fold by alteration that is too slight
to be observed upon ordinary examination. Noticeable alteration causes an
enormous increase in the quantity of gas. Alteration such as we are now
considering is believed to be a consequence of local enrichment of the
volatiles in the rock or magma at appropriate places in the Earth's crust.

In a series of obsidians both the water content and the vesiculation-
temperature relationship were determined. These observations raise in-
teresting questions concerning the mechanism of obsidian and rhyolitic lava
flows. Small differences in the water content (tenths of a per cent) make
great differences in the viscosity of such glasses, and for the very "dry"
glasses it is difficult to imagine their flowing at any temperature yet observed
around volcanoes. Moreover, given sufficient water to be able to flow,
we should ordinarily expect much pumice or even an explosive action.
Attention is called to the Mono Craters in California where the dry cores
seem best explained by assuming that they were carried along by "wetter"
envelopes which by explosive eruptions furnished the main mass of the
structure. Because the rate of diffusion of water in these glasses shows no
abnormal speed, and also because it is difficult to account for the dryness
of the cores by any differentiation or cooling-down process that would leave
the outer layers richer in water, we incline to the hypothesis that such
masses as a whole represent reactivated material — rehydrated masses for
which the process has not had time to penetrate evenly throughout the mass.
This reactivation of dormant magmas may result from local enrichment in
volatiles brought about by the movement of fresh magma in depth, with
corresponding shifting of both volatiles and geotherms.

Attention is called to experiments which indicate that for the acid glasses
and equally for the "mother-liquor" of a crystallizing magma, the loss of
volatile constituents causes a very sudden change of viscosity from a
relatively fluid to a very rigid state. Since the quantity of water needed to
liquefy silicate mixtures at relatively low temperatures is small (at least
for the more acidic magmas), it is possible that reactivation and remelting
of suitably trapped masses of injected country rock are more frequent than
has been supposed.

GEOPHYSICAL LABORATORY 109

Our observations on obsidians are in complete accord with the results
of other studies [Goranson] on the solubility of water, at high pressure,
in magmas of rhyolitic and granitic composition. From these results and
from the determinations of the water present in unaltered rocks it appears
that the primitive, deep-seated magmas are not necessarily highly charged
with volatile constituents and that a high content of "volatiles" is more
likely to be caused by a process of local concentration and enrichment,
which in volcanic regions may be a factor of especial importance.

Sublimates. Upon examining sublimates such as those that occur around
volcanoes and fumaroles, or appear in the cooler parts of the laboratory
apparatus used for pumping gases out of rocks, we find many elements which
the chemist ordinarily regards as non-volatile. For the most part these
sublimates have been formed at temperatures so high that water is more
likely to behave as a gas and that chemical effects such as hydrolysis may
be ruled out. At the present time we do not know sufficiently well which
elements are volatile under the assumed conditions, nor in what form they
may separate from a heated rock. The volatility has usually been ascribed
to the formation of sulfides or halides. It is possible that in some instances
hydrides are produced in the presence of reducing agents, under which
conditions it is not impossible that nitrides may also be present. Although
something is known concerning the vapor pressure of pure oxides and
sulfides, much more work will be required before we can obtain an adequate
understanding of the role played by these compounds in various geologic
processes.

The occurrence of volatile compounds undoubtedly is an important factor
in the processes by which various elements can be concentrated in nearly
pure form and thus made available for practical use. From the analysis
of many thousands of rocks it is known that 8 elements constitute 99%
of the Earth's crust. These elements, in order of their abundance, are
oxygen, silicon, aluminum, iron, calcium, sodium, potassium, and magnesium.
The other 84 elements occur in notably small amounts and if, as believed
by many, the Earth was quite homogeneous at the time of its formation,
the concentration of the rarer elements must have taken place by sub-
sequent physical-chemical processes. Just as various types of rocks are
believed to have been formed by differentiation from a homogeneous parent
magma, so on a smaller scale but in a more complex manner the various
minerals containing one or more elements have been concentrated through
processes of solution and solidification, or volatilization and deposition.

Acid gases play an important part in the activity observed in the vicinity
of volcanoes and fumaroles. Although the principal constituent of volcanic
gases is always water vapor, notable amounts of hydrochloric and hydro-
fluoric acids, hydrogen sulfide, carbon dioxide, and other compounds such
as boric acid, are found in some incrustations. The barium content was
found to be one hundred times that observed in the adjacent pumice. This
furnishes a striking example of the concentration of the minor elements by
processes taking place before our eyes.

Well-defined crystals of magnetite (Fe304) occurring in some incrustations
were subjected to chemical analysis and found to contain elements other

110 CARNEGIE INSTITUTION OF WASHINGTON

than the iron and oxygen. Among these elements were lead, copper, molyb-
denum, tin, antimony, titanium, zinc, nickel, cobalt, and manganese. By
further study of various incrustations the presence of still other elements
was demonstrated. Nearly all these elements have one characteristic in
common — that their halides, and in some cases also their sulfides and
oxides, are appreciably volatile at the temperatures prevailing in fumarolic
gases at the time they are emitted. There is little doubt that the volatility
of various metallic compounds is an important factor in the segregation of
elements originally present as mere traces in the igneous material and in
the formation of mineral deposits of economic importance.

EQUILIBRIA IN SYSTEMS CONTAINING WATER AND OTHER

VOLATILE COMPONENTS

Boron oxide — water. The equilibrium diagram of this system has been
established and the results prepared for publication [Kracek, Morey, and
Merwin]. Boron trioxide is a constituent of many minerals occurring in
nature under conditions that indicate widely differing modes of origin. In
industry borates are used as constituents of enamels and special-purpose
glasses. The presence of B203 in these products imparts toughness and other
beneficial properties, such as low coefficient of expansion, and resistance to
devitrification. Unusual experimental difficulties are encountered in the
investigation of some parts of this system. At high B203 concentrations
the solutions are very viscous and equilibrium is attained only after long
periods of time; at other concentrations the occurrence of metastable com-
pounds complicates the interpretation of the measurements.

The crystalline phases which occur in this system are ice, H3B03, three
modifications of HB02 (monotropically related to one another), and B203.
The freezing-point — solubility curve for H3B03 rises smoothly from the
ice-H3B03 eutectic to a maximum at the metastable melting-point of H3B03,
170.9° C, and then descends to the metastable eutectic for H3B03 and one
of the metastable forms of HB02.

Crystalline B203 was formed from solution in silica tubes, and also in open
vessels at atmospheric pressure, by establishing the conditions necessary
for spontaneous crystallization. The oxide never crystallizes spontaneously
from the nearly anhydrous melts of vitreous B203. Curiously enough, crys-
tallization appears to be initiated by the presence of the stable form of
HB02 but not by the other modifications of this compound. Boron trioxide
melts at 450°. Its solubility curve has been determined from the melting-
point down to the intersection of the curve for the stable modification of
HB02 (at 235°C) and also to the metastable eutectic involving the second
modification of HB02. From the slope of the solubility curve the latent
heat of fusion of B203 has been estimated to be 97 calories per gram.

Boron trioxide is an unusually interesting substance. In its vitreous form
it is tough rather than brittle, and this property appears to be shared to a
considerable extent by the crystalline form which, although lying below steel
on the hardness scale, resists crushing to an extraordinary degree. Like
the other boron compounds in this binary system, the crystalline form is
denser than the liquid or glassy form. Further investigations on the optical

GEOPHYSICAL LABORATORY 111

properties are in progress, but it has already been established that the crys-
tals are nearly or quite uniaxial, with the highest index of refraction equal
to about 1.65.

Calcium sulfate — water. During the past year the work on the system,
CaS04 — H20, has been completed [Posnjak]. Of the solids appearing in
this system, gypsum, anhydrite, and hemihydrate are of considerable tech-
nological importance, and the first two are minerals which present also much
geological interest on account of the occurrence of gypsum and anhydrite in
many sedimentary deposits. The conditions governing their formation have
been the subject of numerous investigations; the most extensive of which
was carried out almost forty years ago by J. H. van't HofT and his associates
as part of their classical work on the formation of the Stassfurt salt deposits.
But later investigations of the system, CaS04 — H20, did not always confirm
the earlier work. The present research on the controversial problems has
shown that the results that were based entirely on indirect determinations
of vapor pressures are erroneous. No dissociation reaction of gypsum to
anhydrite, or gypsum to "soluble anhydrite," takes place. On the contrary,
when gypsum dissociates under ordinary conditions, hemihydrate (plaster
of Paris) is invariably formed.

In the system, CaS04 — H20, reliable information on the relationship of
the various phases has now been obtained directly from solubility data.
The geologically important transition point, gypsum-anhydrite-solution-
vapor, lies at 42° C. It has been shown that, contrary to van't Hoff's con-
clusion, deposition of anhydrite at ordinary temperatures does not require
a high concentration of salt solutions, but may take place even in fairly
dilute solutions, depending on the extent to which the relative solubilities
of gypsum and of anhydrite are affected by added salt. This finding bears
directly on the definition of the conditions necessary for the formation of
deposits of gypsum and of anhydrite of marine origin. Experiments are
now in progress to determine the effect of sea water on the stability relations.

Sodium disilicate — water. Our apparatus for quenching silicate mixtures
in steam under high pressure has given satisfactory results. Experiments
have been made at pressures up to 2500 pounds per square inch. The electric
furnace is enclosed in a gas-tight bomb of stainless steel 6 inches in external
diameter, closed at top and bottom by stainless steel covers, and the joint
made tight with a gold washer. A system of baffles entirely eliminates
trouble from convection currents.

Among the simple systems containing volatile components are the binary
and ternary systems composed of water together with silicates of the alkali
metals. We are especially interested in the upper part of the solubility curves
in such systems and are investigating the lowering of the freezing-point of
some silicates by the addition of water. The system, H20 — Na20 — Si02, is
being investigated and the results for the pressure — temperature curve of
the binary system, water — sodium disilicate, have already been completed
[Morey and Ingerson] . Sodium disilicate, which in the absence of water melts
at about 875°, under increasing steam pressure melts at successively lower
pressures, the lowering of melting point at 2000 pounds per square inch being
145°. As the temperature falls, the rate of pressure increase becomes greater,

112 CARNEGIE INSTITUTION OF WASHINGTON

but a pressure maximum, which is to be expected from various considerations,
has not yet been reached. Special experiments with sodium metasilicate
showed that the volatilization of sodium oxide with steam was too small
to be detected.

Sodium hydroxide — water. A systematic investigation of the important
5-component system, Na20 — K20 — A1203 — Si02 — H20, obviously requires a
thorough knowledge of the various binary systems. Strangely enough,
adequate information on the simple system, NaOH — H20, has not hitherto
been available. An apparatus has now been devised for stirring and filtering
mixtures of these two components while they are maintained at a moderate
temperature and pressure. The liquidus temperatures near the melting-
point of sodium hydroxide monohydrate at 65° have been measured, and a
part of the system, NaOH — Na2C03 — H20, has been investigated [Morey
and Burlew] .

Systems containing two volatile components. Such systems are of interest
for several reasons. The general problem involving the presence of two
volatile components is one that must be considered in nearly all geologically
important cases of transport of material through a vapor phase. Special
interest attaches to the combined behavior of the components H20 and C02
because in the study of systems containing soda or potash the presence of
carbonates is inevitable whenever the alkali content becomes greater than
that corresponding to metasilicates. The vapor phase will contain both
water and carbon dioxide, and the relative proportions of the two under
varying conditions must be determined. The inclusion of carbon dioxide
as a component, therefore, not only constitutes an important step in our
program, but is inevitable on account of the chemical behavior of the
materials in the laboratory. Some important studies in this field [Morey
and Fleischer] are nearing completion.

Behavior of solutions under high pressure. The study of the effect of
moderate pressures on liquid solutions has been continued, the object being
to correlate the effect of pressure on solubility, the volume changes on
mixing, and the compressibilities of aqueous solutions with known properties
of the pure components. Three main lines have been investigated during
the year.

(1) At various pressures up to 1000 bars, and at ten-degree intervals
between 25 and 65°, we determined the compression of the non-polar liquid,
benzene. From the data important thermodynamic constants of benzene
were computed [Gibson and Kincaid] . The results threw considerable light
on the constant B in the Tait Equation, k = C log(l+P/Z?), which we have
used for extrapolation of results along the pressure axis. By analogy with
van der Waals' equation, B appears to represent the difference between the
pressure set up by the intermolecular attractive forces in the liquid and the
thermal pressure. In the same work a new method was developed for deter-
mination of the effect of pressure on the refractive index and dispersion of
benzene, and good results were obtained. Conclusions as to the most suitable
empirical equations for representing the effect of pressure on the refractive
index are in accord with recent work by other investigators.

(2) Hitherto our work on the compressions of solutions has all been at

GEOPHYSICAL LABORATORY 113

25°, but this year a start was made on a study of the effect of temperature
on the compressions of water and aqueous solutions [Gibson and Loeffler].
In order to supply data on the volumes of solutions at 1 atmosphere at
temperatures between 25 and 100° a weight dilatometer of quartz was de-
veloped and has given excellent results. The specific volumes of water and
of solutions of sodium chloride and sodium bromide over the entire concen-
tration range have now been measured at 1, 500, and 1000 bars at temperature
intervals of 10° between 25 and 85°. It is of interest to note that the
apparent volume — temperature curves for these salts pass through maxima
below 95°.

(3) A study of our previous results and of the results of the current work
has been made for the purpose of finding what generalizations may be made
concerning the effect of pressure on the solubility of solids in liquids. In
this analysis several interesting relations were discovered, and it was con-
cluded that sparingly soluble polyvalent salts must have their solubilities
in water raised by pressure and that the pressure coefficient of the solubility
of these substances, while it decreases slightly from 25 to 70° (approxi-
mately), increases as the temperature is raised above 70°.

NON-AQUEOUS SYSTEMS

Albite — nephelite (carnegieite). An investigation of the phase relations in
the binary system, albite — nephelite, has been completed [Greig and Barth] .
At 1254° nephelite inverts reversibly to the modification, carnegieite, which
melts at 1526°. Systems containing compounds with an inversion afford an
important test of solid solution. Upon addition of the second component
to the substance, if more of the second component dissolves in the low-
temperature form than in the high-temperature form, the inversion tempera-
ture is raised. On the other hand, if more dissolves in the high-temperature
form, the inversion temperature is lowered. Very few examples have been
completely worked out, but this system provides an interesting illustration
of the above principle. By the addition of albite to nephelite, the tempera-
ture of the transition is steadily raised and reaches 1282° at the limit of
solid solution, which at this temperature corresponds to 16 weight per cent
albite in the albite-nephelite mixture. Considerations based on crystal
structure indicate that it is not probable that a second component will enter
into solid solution to a like extent with two crystalline modifications of the
substance. The occurrence of solid solution, therefore, can usually be
detected by a change in the inversion-temperature. In the present instance
more solid solution takes place with nephelite than with carnegieite.

Pure albite melts at 1118°, according to the most recent determination,
and is remarkable for the slowness with which the crystalline material
changes to liquid at temperatures even a considerable distance above the
melting-point. Our experience with silicates indicates that the persistence
of the crystalline state at temperatures above the melting-point is a general
property of silicates and possibly of all matter in the solid state, the behavior
of various materials constituting a difference in degree rather than in kind.

An actual determination of the melting-point of a substance like albite
requires special care. It is important to recall that the melting-temperature

114 CARNEGIE INSTITUTION OF WASHINGTON

of a crystalline substance (that melts congruently) is the temperature at
which it can coexist in equilibrium with a liquid of the same composition,
and that above this temperature the equilibrium state is one of complete
liquidity, and below it of complete crystallinity. For substances whose
fusion reaction proceeds so rapidly that they can not be heated appreciably
above their melting-temperature without melting, a failure to observe fusion
at a given temperature is sufficient indication that this temperature is below
the melting-point. On the other hand with a material like albite, although
the fact that it has melted at a given temperature shows that the melting-
temperature has been exceeded, failure to obtain melting does not show that
the melting-point has not been exceeded. A definite criterion is the growth
of crystals. If this takes place, we know that the temperature at which the
growth occurs is below the melting-point. The procedure then is to find a
temperature at which crystals of albite, for example, change to albite liquid,
and a second temperature at which they definitely increase in size, sur-
rounded by a liquid of the same composition. Small crystals of albite were
grown in a homogeneous glass of albite composition. Material so prepared
was held at a chosen temperature and then by means of the petrographic
microscope compared with the original material. An unmistakable change
in the size of the albite crystals indicated whether the chosen temperature
was above or below the melting-point, which could thus be shut in between
two limiting temperatures. Obviously the spread between these two limits
can be narrowed to any desired extent by holding the material at a series of
constant temperatures for a sufficiently long time.

On the basis of composition the mineral jadeite, Na2O.Al203.4Si02, be-
longs in this binary system, but jadeite was found not to be stable in contact
with the liquid, and does not appear in the equilibrium diagram within the
temperature range that has been investigated. Jadeite does not occur in
the common igneous rocks and has been considered by petrologists to be
stable only at high pressures.

Leucite — diopside — silica. Special interest attaches to the melting phenom-
ena of olivines and pyroxenes, which are among the early minerals to crys-
tallize from a cooling magma, and of the alkali-alumina silicates which are
among the late minerals. We have been studying the behavior of systems
which combine one of the early-forming minerals with late-formed minerals,
in order to ascertain the nature of the residual liquids from fractional crys-
tallization of such systems. Measurements have now been completed for
the system, leucite — diopside — silica, which combines one of the simplest
pyroxenes, diopside, with the alkali-alumina silicates, leucite and potash
feldspar [Schairer and Bowen]. In this system there are no ternary com-
pounds. The field of diopside occupies a large part of the ternary diagram,
and with mixtures containing even less than 2% diopside in total composi-
tion, diopside appears as the primary phase. Ordinarily, therefore, upon
crystallization diopside is removed almost quantitatively, leaving residual
liquids that in composition approach a mixture of potash feldspar and silica.

Rock-forming pyroxenes. These are among the most complicated minerals
of the igneous rocks. They are polycomponent solid solutions involving the
compounds, CaSi03, MgSi03, FeSi03, MnSi03, in addition to A1203, Fe203,

GEOPHYSICAL LABORATORY 115

and often Ti02. During the past year exploratory studies were made to
ascertain if it was possible to obtain equilibrium data on silicate mixtures
containing, among other things, FeO and A1203. A study of mixtures on the
join, anorthite — fayalite, showed that these mixtures are quaternary in
their behavior but amenable to study by the method of quenching in iron
crucibles in an atmosphere of nitrogen. The preliminary results suggested
that the first step in determining the role of A1203 in the augite was the
complete study of the fundamental system, FeO — A1203 — Si02. This has
been undertaken and very substantial progress has been made on it. In
this system no ternary compounds appear on the liquidus surface. During
the coming year the investigation will be pressed to completion, and experi-
ments will be started on portions of the quaternary system, CaO — FeO —
A1203 — Si02, the next step in the attack. It is worthy of note that the system,
FeO — A1203 — Si02, is of interest not only to the petrologist but also to the
metallurgist. Many blast furnace slags from high-alumina ores approach
compositions in this system.

Alkali-alumina silicates. Among the silicate systems just completed is
the system, K20 — A1203 — Si02, which was begun in 1932 and has required
six years of continuous effort to complete. The diagram for this system
depicts the complete melting relations of the two important rock-forming
minerals, leucite (KAlSi206) and potash feldspar (KAlSi308). Measure-
ments on nearly 450 different compositions were required for the complete
melting diagram, which shows the behavior of these minerals with either
an excess of alkali or of alumina. This system and the system, Na20 —
A1203 — Si02, (which is now well along toward completion) are directly
applicable to many fields of chemical technology, such as the glass and the
ceramics industries.

Other systems. Among other systems the investigation of which has
been completed are the binary systems, wollastonite — diopside and wol-
lastonite — akermanite, and the ternary system, nephelite — fayalite — silica.
The systems, soda — alumina — silica, leucite — anorthite — silica [Schairer and
Bowen] , potassium disilicate — sodium disilicate [Kracek] , and gold — silver
— tellurium [Tunell, Ksanda, and Kracek] , are either practically finished or
rapidly approaching completion.

SPECIAL PHYSICAL METHODS FOR THE STUDY OF STRUCTURE

AND PROPERTIES

X-ray methods. Improvements in experimental technique have facilitated
the use of X-ray methods in our research problems and have permitted the
application of these methods to a great variety of substances. Although
the study of organic substances seems far removed from silicate research,
it is of interest and importance to study the orderly arrangement of simple
crystals formed at moderate temperatures merely by the laying of one
molecule against another, in contrast with the complex rock-forming minerals
formed at much greater temperatures. Careful study of a few fundamental
types should lead to generalizations governing that enormous and continually
increasing number of organic substances with which the progress of modern
organic chemistry has made us familiar, and quantitative data concerning

116 CARNEGIE INSTITUTION OF WASHINGTON

the molecular symmetry of simple compounds should give aid in the inter-
pretation of structures of a more complex nature.

Recent determinations [Ksanda and Tunell] of the unit cell and space-
group of glycine (one of the simplest of the organic compounds) have not
only aided in the physical-chemical study of the system, glycine — water,
under high pressure but have also yielded results of interest from the stand-
point of crystal structure. Crystals of organic substances are frequently
of low symmetry or are completely asymmetric. Consequently the majority
of organic substances crystallize in the monoclinic system. Since the scat-
tering powers of carbon, nitrogen, and oxygen are very nearly the same,
they can not be distinguished with certainty by X-rays ; moreover, the deter-
mination of the change of atomic positions with the state of chemical com-
bination is difficult. The atomic arrangement in most organic crystals —
consisting of many parameters — forms a structure that is bound molecule to
molecule by forces of weaker nature than those existing between the atoms
in gaseous molecules.

A study of samples of tungsten wire 0.115 mm diameter, from which the
springs for our gravity meter are made (see below) , was carried out by means
of X-rays. The pinhole method, with a circular camera and monochromatic
Cu-K radiation filtered through nickel foil, was used. A series of photo-
graphs, under the same conditions of exposure and development, was taken
of (a) drawn tungsten wire, previous to forming into the desired shape,
slightly annealed but not heat-treated, (b) part of a finished spring, heat-
treated at 1200° C. for two hours in a specially built furnace, in which the
air was displaced by hydrogen, and (c) part of a finished spring, heat-treated
for two hours at a temperature of 1300° C.

The diffraction lines in (a) are uniformly broad, and the lines of higher
planes show no resolution of Ro^ and Kct2 doublet — thus indicating residual
deformation of the lattice arrangement. This deformation causes variable
atomic spacings and a departure of the oriented particles from perfect
alignment.

In (6) the diffraction lines are sharp and of uniform density, and the
reflections from planes hkl 123 and 400 begin to resolve into the ax and a2
doublet, which indicates that recrystallization to a fine crystalline structure
consisting of grains oriented perfectly at random has taken place. The
physical properties of such a structure should be nearly the same in all
directions. In tests and practical use, a spring receiving such heat-treat-
ment was found entirely satisfactory. Heat-treatment at higher tempera-
tures produced a structure having larger size crystals, evidence of which is
noticeable in (c) ; the diffraction lines in this spectrogram are beginning to
show a pronounced Laue effect. A spring heat-treated at a temperature
above 1200° C. was found to be unduly brittle.

Measurement of diffraction lines of these films and the unit cell dimen-
sion calculated from them (with correction applied for unresolved diffraction
lines) gives the value for a0 = 3.158 ± 0.005 A. Metallic tungsten has a
body-centered type lattice, and belongs to space-group Oh9 — m3m. There
are two molecules of W in the unit cell.

GEOPHYSICAL LABORATORY 117

The annealing temperature and the heat-treatment of tungsten wire used
for springs are very important and determine the mechanical properties of
the finished spring. Heat-treatment under controlled conditions produces
a marked effect on the lattice arrangement and the size of the grain.

Raman spectra. The work of the past year has been a continuation of
the attack on the general problem of molecular constitution by spectroscopic
methods [Hibben]. To this end several types of compounds were investi-
gated. The first group consisted of methyl methacrylate and its polymers,
and diethyl fumarate and maleate. These substances give Raman spectra
containing a number of lines characteristic of the molecular constitution.
The presence of the ethylenic (C = C) grouping is shown by the Raman

shift near Av 1650 cm-1, and the C = structure by some vibrations above

Av 3000. On comparing the relative intensities of the carbonyl (C = 0)
displacements with the ethylenic ones, we conclude that the unpolymerized
methyl methacrylate is more closely related to the cis isomers than to the
trans isomers. In the polymers of methyl methacrylate, which form organic
glasses, the ethylenic and the hydrogen displacements are completely absent.
This shows that polymerization takes place through the unsaturated carbon
atoms, with the production of large molecular aggregates which tend to form
glasses. It is highly probable that the inorganic silica glasses are built up
in the same manner. These experiments also show the enormous effect of
a small amount of polymerization on the viscosity of liquids.

Another group of compounds investigated included zinc chloride, which
possesses a valence that may be homopolar or heteropolar. In dilute solu-
tions it ionizes to zinc and chlorine ions. The spectrum of a concentrated
solution of this compound indicates that the ionization in such solutions
is repressed and that a large portion of the molecules exist in the un-ionized
state. The addition of a common chloride atom was found to repress still
further the ionization, while other zinc salts had little effect.

A pair of closely related isomers, a-methyl glucoside and a-methyl man-
noside, was examined. The spectra obtained for these two substances are
entirely different, although there is a common general pattern. The 180°
rotation of one of the H — C — OH groups around the central axis disturbs
the symmetry of the molecule and alters the whole spectrum. This result
is important because it shows that the specific heat — which depends on
these vibrations — and other physical properties may be changed profoundly
by a slight change in symmetry.

From the results of a study of boric acid and its salts it was concluded
that boric acid is a molecule of the type AB3 having the symmetry D3h in
which all the B groups lie at the corner of a plane triangle with the boron
atom in the center, and that the B02 ion is non-linear and has a bent structure
with the symmetry C2V- Sodium tetraborate was found to dissociate, on
solution, into sodium metaborate and boric acid. Sodium hydroxide when
added to boric acid solutions causes the immediate formation of sodium
metaborate, and hydrochloric acid added to an aqueous solution of sodium
tetraborate produces boric acid. All these changes may be demonstrated

118 CARNEGIE INSTITUTION OF WASHINGTON

by means of the Raman effect without affecting the condition of the solu-
tions. The spectrum of crystalline sodium tetraborate is consistent with
the view that both crystals and glass are made up of long chains of B03
and B02 groups.

The most recent investigation in this field is the critical and detailed
study of crystals of the type represented by calcite, aragonite, and barite.
A number of new Raman lines found in these crystals are combinations and
harmonics of other lines some of which are "forbidden" as fundamentals in
the Raman effect. When the complete spectra are obtained it may be pos-
sible to coordinate the spectra with the specific heats of the compounds,
for there are several lattice vibrations which undoubtedly contribute to the
specific heat. The effect of temperature on the Raman spectra of crystals
is being studied.

Optical methods. Probably the most nearly indispensable tool in silicate
research is the petrographic microscope. With this instrument precise
measurements for purposes of identification are made on minute fragments
of materials by the use of an elaborate technique that was devised many
years ago and subsequently has been continuously developed and improved.
An important class of measurements depends upon observations of inter-
ference figures in crystals through which polarized light is passed. Crystals
of many compounds are so strongly birefringent and dispersive that inter-
ference figures obtained by illumination with white light are indefinite.
In monochromatic light a clear set of black curves may be seen but not the
order of interference or the direction of its change. A significant improve-
ment in the examination of such materials has been made [Merwin and
Greig] by selecting filters that transmit a band of sharply contrasted colors,
e.g. orange to yellow-green, or by choosing a filter or combination of filters
that transmit two very narrow bands, e.g. red and green.

Optical determination of the constituents of clays and other deposits,
such as those4 of the floor of the ocean, offers special difficulty and requires
the application of special methods. Careful examination of the ocean-
bottom samples collected by the Carnegie revealed the presence of dolomite
in widely separated areas in the Pacific Ocean far removed from land
[Merwin and Posnjak]. It becomes evident that the composition of the
sea water is such that dolomite can and does deposit directly from solution.
The fact that dolomite can be produced directly rather than by replacement
throws light upon an important class of sedimentary deposits.

Increasing use of the methods of petrofabric analysis is being made in the
investigation of rocks. Important advances in technique whereby the three-
dimensional arrangement of mineral grains and various details of structure
are accurately fixed with reference to the original orientation of the specimen
[Ingerson] allow us to infer the kind of movement that has taken place in
masses of deformed rock.

Electrical properties of multilayers. Crystalline substances found in
nature are electrically neutral. This is due to the circumstance that al-
though in the crystal lattice there may be molecules present which possess
permanent electrostatic moments, such molecules are grouped in pairs or

GEOPHYSICAL LABORATORY 119

sets so arranged that an internal compensation of their electrical fields
takes place.

Recently, in connection with their discovery of a method of producing
multilayers of long chain molecules, Langmuir and Blodgett of the General
Electric Company succeeded in depositing on metal surfaces as many as
3000 layers of molecules. They found it possible to prepare two types of
multilayers of calcium stearate, called the Y type and the X type. In the
Y type multilayer, although all the molecules in one layer are oriented alike,
the molecules in the adjacent layer are oriented in the opposite direction,
whence the electrical fields due to the first, third, and fifth layers, for
example, are compensated by the electrical fields of the molecules in the
intermediate layers, that is, the second, fourth, and sixth. The structure of
a Y multilayer of calcium stearate was found to be precisely the same as
that of ordinary calcium stearate. From their experimental results they
also concluded that the molecules in the X type multilayer of calcium
stearate were all oriented in the same direction.

Subsequently, Porter and Wyman of the Harvard Biological Laboratory
reported that the X type of multilayer, when deposited on chromium, was
characterized by an electrical field which in their experiments produced a
potential difference of 8% volts, with about 160 layers. From these results
we inferred that the electrical phenomena found by Porter and Wyman
were a demonstration of the existence of a lack of compensation in the
electrical fields of the molecules in the X type multilayer. In conformity
with the structural ideas advanced by Langmuir and Blodgett, we concluded
also that since this would mean a volume polarization of the X type multi-
layer, such a material, if deposited on a non-conductor and suspended in an
electrical field, would develop a rotation which would be proportional to the
electrical field, to the area coated with the layer, to the number of layers in
the multilayer, and to the electrical moment of the individual molecule.

Although there have been many attempts to produce a permanent volume
polarization in crystals for the purpose of obtaining the electrostatic
analogue of a permanent magnet (the electret, about which Oliver Heaviside
speculated years ago), no one had succeeded in producing an electret with a
polarization strong enough to be of practical value. Our calculations, based
on the results of Langmuir and Blodgett, as well as those of Porter and
Wyman, showed that the rotations one would expect to observe were large
enough to be measured, and possibly might be large enough to prove of use
in the construction of indicating instruments.

In the earlier work X type layers were deposited only upon polished glass
and certain polished metals. We were able to produce the deposits upon
mica, ebonite, cellulose triacetate, and methyl methacrylate. We also suc-
ceeded in preparing films containing as many as 350 X type layers [Goran-
son and Zisman] , and we have been able to demonstrate that the rotations
observed in an electrical field are of the order of magnitude predicted by our
calculations. In addition, we have observed an interesting phenomenon,
which may be called the "electrolysis effect" and apparently is due to the
presence of ions throughout the volume of the multilayer. Although the
calculated order of magnitude of the electric moment seems to be correct

120 CARNEGIE INSTITUTION OF WASHINGTON

for a moment caused by dipoles, the presence of ions, shown by the elec-
trolysis effect, and the existence of other phenomena that still await ex-
planation, have indicated the need for further measurements of the magni-
tude of the charges within the multilayer. The adsorption of calcium ions
on the surfaces probably accounts for various phenomena reported by other
investigators.

Thermal properties of rock-forming minerals. Little information has been
available concerning the specific heats and the heats of fusion of the silicates.
In view of the growing emphasis on the thermodynamic aspects of geologic
problems, it has become increasingly important to develop the facilities for
routine determination of thermal properties as they become needed.

Unlike the metals, most silicates fail to crystallize when melted and
suddenly cooled. Consequently the "dropping method," which depends on
measuring the heat liberated when the melt crystallizes, is not generally
applicable. Thermochemical means have been employed in selected cases,
but such methods are difficult and may be subject to concealed errors that
must be evaluated or proved negligible before the results can be accepted
with confidence. At low temperatures, heats of melting are quite commonly
determined by a direct measurement of the energy that must be supplied to
a sample in order to transform it from solid to liquid. It seemed probable
that, at the much higher melting-temperatures of the silicates, this direct
method would be subject to serious errors due to thermal and electrical
leakage and that measurement and adequate control of temperature would
be difficult. On the other hand it seemed likely that by careful design of the
apparatus these errors might be reduced to a point where adequate data
could be obtained in a large proportion of cases.

Accordingly a preliminary study of the method was begun, using, for the
most part, existing laboratory equipment. As stated in the Annual Report
for last year, enough information was thereby obtained to warrant building
the specialized apparatus needed for routine determinations at temperatures
below 1300°. This apparatus is now in operation, and the heats of melting
of K2S04 and Na2Si03 have been determined [Roberts] at their respective
melting-points (1069° and 1089°). Data obtained in making several deter-
minations of each of these quantities indicate that we may expect an uncer-
tainty probably not greater than 5 per cent in determinations made below
1200° or possibly 1300°. At still higher temperatures the relative impor-
tance of the various corrections is so great that a modified apparatus will
probably be desirable.

FIELD WORK

Ocean-bottom sampling. For the purpose of securing additional cores from
the ocean-bottom, and especially from the great deeps where the bottom
lies more than 5 miles below the surface of the water, a portable sounding
apparatus has been obtained and is now being put in working order for
early use on board ship [Piggot] . The apparatus consists of a winch with
5200 fathoms of steel cable, operated by a Diesel engine having sufficient
power to reel in the cable at an average speed of 300 feet per minute.
Features that will expedite the difficult task of lowering to the bottom the

GEOPHYSICAL LABORATORY 121

heavy combination of sampling device and cable and bringing the sample
back to the surface are (1) a hydraulic brake used separately or in con-
junction with a mechanical brake, (2) a spooling device with continuously
variable ratio, and (3) a special shock absorber, or torque arm, for reducing
the strain on the cable caused by the pitching or rolling of the ship.

Because a steel cable of uniform section 5000 fathoms long, hanging freely
from one end, is not sufficiently strong to support its own weight (with any
reasonable factor of safety), recourse was had to a suitable "tapered" cable.
This consists of six sections varying in size from %6 inch to % inch in
diameter, the smallest section being at the bottom end and the various
sections being carefully spliced together. From tests of tensile strength
it was found that we have a factor of safety of three. The winch is supported
on a base approximately 6 feet by 9 feet, and the combined weight of winch
and cable is about 12 tons.

Volcanological studies at Montserrat. An important phase of the volcano-
logical program has been the investigation of the volcano on the island of
Montserrat by Research Associate F. A. Perret in cooperation with the
Geophysical Laboratory. Additional observations of the volcanic and
seismic activity on this island have been supplemented by studies on a new
and similar phase of activity at Dominica. The volcanoes of the Lesser
Antilles, with their accessible peaks, continuing activity, and alternating
periods of volcanic and seismic phenomena, have afforded a valuable op-
portunity for research in this field. A new type of microphone, constructed
as a complete and self-contained unit and well adapted to volcanological
research, has been developed. Continuous records of sulfide gases were
obtained at Montserrat and the new shock-recorder, or "seismeter," was
installed at Dominica. The success attained through the use of these
instruments at various centers has served to emphasize the great advantages
of quantitative measurement in the study of volcanoes. The complete
report of the observations at Montserrat which has now been prepared for
publication marks a definite advance in our knowledge of the behavior of
volcanoes.

Gravity measurements. The new gravity torsion meter referred to in the
Annual Report of last year has been built in the Laboratory and is now
ready for thorough test in the field [Wright and England]. In the new
design the effort has been made to produce a lighter and more compact
instrument with effective insulation and with all parts easily accessible.
The principle of the instrument has, however, remained unchanged; the
torsion element is kept at constant temperature and under constant reduced
air pressure of one millimeter of mercury; it is, moreover, placed under
strain only during the four to six minute period required to occupy a station.
At other times it is held at rest in order that the strains introduced during
a measurement may be dissipated. As a result of this careful treatment of
the torsion element the readings of the old instrument remained constant
for any given station to one part in a million over an eight-month period
of field test during which many stations were occupied.

In the new instrument the housing is made of an aluminum alloy of high
mechanical strength, the optical system and the graduated circle and

122 CARNEGIE INSTITUTION OF WASHINGTON

vernier arc are mounted inside the housing, and the rotating support for
the torsion spring is a single casting. The levels are attached to the housing
and can be viewed through a single lens tube without disturbing the in-
strument. The housing is encased in well-insulated stainless steel drums.
Constancy of temperature is maintained by use either of ice or of an
electrically heated thermostat. For field use the instrument is carried in
a light motor truck with insulated walls. To occupy a gravity station the
apparatus is shifted to a heavy tripod that reaches through the floor of
the truck to the ground. Measurements can then be made inside the truck
regardless of weather conditions.

Projected volcanological investigation in Central America. This is a
region containing an unusual number of active volcanoes. Preliminary
studies in 1932 and 1935 showed many features of interest and pointed to
the desirability of a thorough and systematic investigation of volcanic
activity in a selected area in the region. Detailed plans have been worked
out for field studies in cooperation with other agencies and it is hoped that
funds will become available for this program. It is possible to learn some-
thing of the underground structure in the vicinity of an active volcano by
the application of modern physical methods. Measurements of gravity
with our portable gravity meter, magnetic surveys, measurements of Earth
resistivity, chemical studies of volcanic products, and an investigation of
the pertinent geologic relations are the principal methods by which we ex-
pect to gain further information on the origin of volcanoes and the nature
of volcanic processes.

SUMMARY OF PUBLISHED WORK

(947) A bomb for use in hydrothermal experimentation. George W. Morey and Earl Inger-

son. Amer. Mineral., vol. 22, pp. 1121-1122 (1937).

An illustrated description of an improved bomb for use in hydrothermal experi-
mentation.

(948) The availability of optical glass in America. George W. Morey. Jour. Optical Soc.

Amer., vol. 28, pp. 5-7 (1938).

Optical glass is the material available to the designer for the calculation and
construction of lens sj^stems in which the many possible defects and aberrations are
reduced to a minimum. It is characterized by the perfection of certain physical
properties, obtained by extreme care in manufacture, and by a wide range of
optical properties, obtained by change in composition.

The physical properties which characterize optical glass are almost perfect
homogeneity and high transparency. Freedom from bubbles is also important,
but in this respect optical glass does not differ from other types of glass such
as ophthalmic glass or even plate glass, and for many uses a few small bubbles
do no harm and are less objectionable than in plate glass.

The optical glass industry in this country at the close of the War had developed
a tremendous potential capacity. The types of glass manufactured were limited
to those few which are the irreducible minimum for military needs, far fewer than
are needed for general optical purposes. Four firms were engaged in the manu-
facture of optical glass, but of these only one has continued production. That
company manufactures a wide range of glass types and could produce any addi-
tional types for which demand might develop.

GEOPHYSICAL LABORATORY 123

(949) Olivine fourchites from Raymond Fosdick Mountains, Antarctica. Clarence N. Fen-

ner. Bull. Geol. Soc. Amer., vol. 49, pp. 367-400 (1938).

A collection of ultrabasic rocks from an extinct volcano had been made by the
Second Byrd Antarctic Expedition and the rocks were brought to the Geophysical
Laboratory for study. Their physical and mineralogical make-up was such as to ren-
der possible a separation of their component minerals. Analyses of the products were
made. With this information, a comparison of the actual course of crystallization
of the magma with what has been deduced from the theory of crystal fractiona-
tion was possible.

The aphanitic groundmass, freed of phenocrysts, was found to have an ultrabasic
composition. Therefore it is concluded that wholly liquid ultrabasic magmas exist.

Comparison of compositions of phenocrystic pyroxene and groundmass pyroxene
shows changes during the course of crystallization that are hardly in accord with
those that have been deduced as generalizations from experimental work and that
have been used in support of the theory of crystal fractionation.

The view is expressed that experimentally investigated systems represent, on the
whole, simpler conditions than exist in natural magmas; and that inferences derived
from the behavior of these comparatively simple laboratory melts have been
broadened and generalized to cover conditions to which they are hardly applicable.

(950) The nature of solutions and their behavior under high pressures. R. E. Gibson.

Scientific Monthly, vol. 46, pp. 103-119 (1938).

In this lecture, delivered at the Administration Building of the Carnegie Insti-
tution of Washington, the broader problems raised by a consideration of matter
in the depths of the Earth are described, together with the methods by which these
questions are broken down into simpler specific problems to which known experi-
mental and theoretical technique may be applied. The problem of the effect of
pressure on solubility is reduced to one of determining either experimentally or
theoretically the volume changes on mixing and the compressibilities of solutions
and their components. The results of a study of the compressibilities and volume
changes on mixing of a large number and variety of solutions (see Laboratory
Papers 839, 843, 870, 883, 918, 926, 941) are reviewed and an attempt is made
to interpret them in the light of current ideas on the nature of solutions. In
particular, the specific effects of different electrolytes when dissolved in water are
discussed and it is pointed out that these effects may be well explained if the
effect of the volumes of the dissolved ions on the internal pressure of the water
is taken into account.

(951) The influence of temperature and pressure on the volume and refractive index of

benzene. R. E. Gibson and John F. Kincaid. Jour. Amer. Chem. Soc, vol. 60,
pp. 511-518 (1938).

The work described in this paper was undertaken by the authors with two
objectives in mind, namely, to examine the Tait equation used for expressing the
volume of a liquid as a function of pressure over a temperature and pressure range
for a simple non-polar liquid, and to try out a new method for estimating the change
with pressure of the refractive index of liquids.

The compressions of benzene to different pressures between 1 and 1250 bars were
measured at 10° intervals between 25 and 65°. The compressions were well repre-

sented by the Tait equation k = C log I ^ land it was found that the

constant C was independent of temperature. From these results important thermo-
dynamic properties of benzene were computed over a range of pressure and
temperature. A study of the temperature variation of the constant B showed

124 CARNEGIE INSTITUTION OF WASHINGTON

that it could be introduced empirically into an equation of state of the van der
Waals' type and that B represented the difference between the thermal expansive
pressure and the cohesive pressure due to the attractive forces between the
molecules.

The method employed for measuring the effect of pressure on the refractive
index of benzene consisted of adjusting the pressure (at constant temperature)
until the refractive index of the benzene exactly matched that of a fragment
of optical glass immersed in it. The match was determined by visual observation
through a microscope, monochromatic light being used. The refractive index of
the glass changed very little with pressure and its change could be computed from
the compressibility of the glass. Measurements were made over a range of 20°
and 1200 bars pressure. The results were fitted exactly by the Eykman equation
which represents the refractive index as a function of the volume; indeed, it was
shown that with the help of the Eykman equation the compressions of benzene
could be computed from the refractive indices at different pressures about as
accurately as they could be measured directly.

(952) Core samples of the ocean bottom and their significance. Charles Snowden Piggot.

Scientific Monthly, vol. 46, pp. 201-217 (1938).

An address delivered at the Administration Building, Carnegie Institution of
Washington, November 23, 1937.

The least disturbed geologic record of the relations which have existed between
the continental elevations and the oceanic basins is the sediment at the bottom
of the sea. Early efforts to study the sea-bottom are briefly referred to and an
apparatus which has secured more adequate samples from great depths is described
in some detail. Certain geophysical problems which may be attacked by an appeal
to this ocean-bottom record are discussed — more particularly the accumulation of
radium in the deep sediments — and the significance of such studies in the future
is considered.

(953) The application of the Raman effect to petroleum chemistry. James H. Hibben.

Reprinted from "The science of petroleum/' Oxford University Press, 1938, pp.
1206-1212.

This is an outline of the elementary theory of the Raman effect and its appli-
cation to the field of petroleum chemistry. It is pointed out that all hydrocarbons
and their derivatives have a characteristic spectrum which depends on their
composition, the valence forces between the atoms in the molecule and the molecular
symmetry or the arrangement of the atoms in space. This permits the identifica-
tion of the components of hydrocarbon mixtures if the mixtures are not too complex.
Even in the latter case it is possible to identify the type of hydrocarbons and their
derivatives. The olefins, cycloolefins, acetylenes, and aromatic compounds have
characteristic Raman frequencies depending on the ring structure and on the
ethylenic and acetylenic type of linkage. The ethers, alcohols, and cyclic com-
pounds may likewise be distinguished.

The principal utility of the Raman effect, however, rests in its application where
other methods are either cumbersome or unavailing. It is possible, for example,
to follow the fractional distillation of naturally occurring terpenes and to determine
the presence of mixed isomers. The type and quantity of olefins occurring in
cracked gasoline can also be estimated.

Apart from these purely chemical applications, information regarding bond
strength, specific heats, and latent heats of fusion is made available from these
spectroscopic data. It is shown that the determination of the molecular consti-
tution of many complex organic compounds can best be made by means of Raman
spectra.

GEOPHYSICAL LABORATORY 125

(954) The technique of securing undisturbed core-samples of the ocean bottom. Charles

Snowden Piggot. Proc. Amer. Phil. Soc, vol. 79, pp. 35-46 (1938).

A ten-minute address given as part of the "Symposium on the Geophysical
Exploration of the Ocean Bottom," held at the Autumn General Meeting of the
American Philosophical Society, Philadelphia, Pennsylvania, November 26, 1937.

Adequate sampling of the ocean bottom below more than 1000 fathoms becomes
increasingly difficult with increasing depth. A sampling apparatus must take
down with it the necessary energy. Such an apparatus is described and the technique
of its successful manipulation below 2600 fathoms is discussed.

(955) Uraninite and associated minerals from Haddam Neck, Connecticut. Earl Ingerson.

Amer. Mineral., vol. 23, pp. 269-276 (1938).

Torbernite has been known from the Rock Landing quarry at Haddam Neck,
Connecticut, but uraninite from that locality has not been described. A recent
find includes two large pieces (6 X 7 X 10 cm. and 2X3X4 cm.) and numerous
smaller fragments of uraninite. It was identified by its crystal form, etch tests,
microchemical test for uranium, its radioactivity, and X-ray determination. An
age determination by Hecht and Kroupa gives a value of about 285 million years.
This is in good agreement with the results of analyses of minerals from other
Connecticut pegmatites and places the time of formation as late Devonian.

Other minerals included in the find are gummite, autunite, torbernite, and
columbite, besides the more common species smoky quartz, muscovite, potassium
feldspar (perthite), black tourmaline, apatite, large beryl crystals, and small
cubes of pyrite.

(956) Rock formation: Nature's chemical industry. George W. Morey. Chemistry and

Industry, vol. 57, pp. 966-971 (1938).

A lecture delivered before a joint meeting of the Society of Chemical Industry
and the New York Section of the American Chemical Society, April 8, 1938.

(957) Crystallization equilibrium in nepheline-albite-silica mixtures with fayalite. Nor-

man L. Bowen and J. F. Schairer. Jour. Geol., vol. 46, pp. 397-411 (1938).

This paper presents the results of a thermal study of the system, NaAlSi04 —
FeO — Si02, and discusses their application to petrology. The crystalline phases
formed in the various compositions are cristobalite, tridymite, albite, fayalite,
nepheline, carnegieite, hercynite, and wustite. There are two ternary eutectics,
one between tridymite, albite, and fayalite (temperature 980 ± 10° C.) which
may be regarded as a simplified fayalite rhyolite, and the other between nepheline,
albite, and fayalite (temperature 990 ± 10° C.) which may be regarded as a
simplified fayalite phonolite. These and other findings are discussed in connection
with the origin of natural phonolite, trachytes, and rhyolites carrying fayalite.

(958) The concentration of the less familiar elements through igneous and related activ-

ity. E. G. Zies. Chem. Rev., vol. 23, pp. 47-64 (1938).

The bulk of the Earth's crust is composed of igneous rocks, and with respect
to its entirety the concentration of the less familiar elements is extremely low.
They assume economic importance only when they have been reconcentrated in
some favorable physico-chemical environment. Some attain this importance when
through the various processes of magmatic differentiation they have accumulated
in the mother liquor from which the pegmatites are derived and combine with other
elements to form distinct minerals. It is quite probable that acid vapors are impor-
tant at this stage of differentiation because the halides, sulfides, and even oxides
of many of these elements are volatile at the prevailing temperatures. Considerable

126 CARNEGIE INSTITUTION OF WASHINGTON

evidence has been obtained that this type of concentration also takes place during
volcanic activity. There is still another method by which a rare element can
accumulate in a favorable environment. It can be segregated within the crystal
lattice of some common mineral because its ionic radius is almost identical with
that of one of the constituents in the mineral. This theory of "camouflage" was
developed by V. M. Goldschmidt and is a useful guide for the analyst in searching
for the rare and less familiar elements.

(959) Laboratory technique of petrofabric analysis. Earl Ingerson. Part II of Memoir 6,

Geol. Soc. Amer., "Structural petrology," by E. B. Knopf and Earl Ingerson, pp.
209-262 (1938).

The methods of fabric analysis are being used more and more in this country.
They are now being taught in several universities as a part of structural geology,
as extra-curricular series of lectures, or as independent courses.

There are several fragmentary accounts in English of the methods of fabric
analysis, but to date no complete, fully illustrated account of the laboratory
technique has appeared. This paper is an attempt to fill the need for such a
manual. The various steps of the laboratory procedure are described and they
are illustrated by photographs of specimens and apparatus, and by drawings.
There are forty-eight illustrations.

The exhaustive study of a single specimen is described, but it is made clear
that for most problems only a part of the complete procedure will be necessary.
Simplifications are suggested.

The following chapter headings indicate the scope of the work: (1) Study of
Hand Specimens, (2) Study of Thin and Polished Sections, (3) Universal Stage
Technique, (4) Preparation of Petrofabric Diagrams, and (5) Rotation of
Diagrams.

(960) Contact relations between rhyolite and basalt on Gardiner River, Yellowstone Park.

Clarence N. Fenner. Bull. Geol. Soc. Amer., vol. 49, pp. 1441-1484 (1938.).

In an area on Gardiner River, a flow of rhyolitic lava had followed a small
valley previously eroded in a basaltic surface. Remarkable contact effects, appa-
rently different in some respects from anything previously recorded, were produced.

In many places, the rhyolite has penetrated deeply into the basalt, as complex
networks of veins and dike-like bodies, which ramify through the basalt in intricate
patterns. Erosive action of the rhyolite flow upon the basaltic surface apparently
brought about modifications of the original channel. The composition of the basalt
near contacts was greatly changed. Basaltic constituents were carried away and
rhyolitic constituents were substituted. Analyses show that the compositions lie
almost exactly on straight lines between basalt and rhyolite.

The behavior of the rhyolite in producing these effects was far from what has
been considered by many geologists as orthodox for such a magma, and in attempt-
ing to analyze the problems presented and find a reasonable explanation, it has
seemed necessary to attribute properties to the rhyolite somewhat different from
those usually postulated. In reaching conclusions, the field observations have been
supplemented with the study of polished specimens and microscopic sections, and
with chemical work. From all the information obtained, it seems most probable
that the medium by which basaltic constituents were carried away was that of the
vapors evolved from the rhyolite. Whatever the medium, the fact that large quan-
tities were thus removed implies large stores of energy in some latent form in the
rhyolitic magma. The rectilinear compositions of modified basalts indicate that all
constituents of the original basalt were present in exactly the right proportions
to satisfy the solution requirements of the rhyolitic medium. This, in turn, implies

GEOPHYSICAL LABORATORY 127

some extraordinary, but unexplained, genetic relationship between the basalt and
the rhyolite.

(961) The properties of glass. George W. Morey. Amer. Chem. Soc. Monograph Series

No. 77, 571 pp., 161 tables, 152 figs., New York, 1938. (Reinhold Publishing
Corporation.)

Glass is a most important application of silicate science to technology, and the
systematic and critical assembly and discussion of the properties of glass will be
of service to silicate science in general, and in particular in its application to
geology.

The properties of glass have long been of interest to the Geophysical Labora-
tory. In the first paper from the Laboratory, Day and Allen made observations
on the absorption of heat in borax glass near its annealing range, which developed
into an active international discussion of the nature and constitution of glass.
The important work of Adams and Williamson on the annealing of glass, which
laid the foundation for modern industrial practice, carried the problem farther,
and the most recent contribution, on density and refractive index, gave us a more
extensive knowledge of the variation of these properties with chemical composition
in glasses than in other types of solutions. Studies from the Laboratory on the
reaction between water and silicates established the theoretical principles underlying
the chemical durability of glass. More recent studies on the phase equilibrium
relations gave us for the first time a knowledge of the factor which made possible
the manufacture of glass in its manifold applications to human needs.

The book is a comprehensive and critical discussion of the literature concerning
the properties of glass, in which attempt has been made to include all measure-
ments on glasses of known composition. Throughout, emphasis has been placed
on physical properties as functions of chemical composition.

(962) Summary of article by Bruno Sander: "liber Zusammenhange zwischen Teilbewegung

und Gefiige in Gesteinen," Tschermak's mineralog. petrog. Mitt., vol. 30, pp. 281-314
(1911). Earl Ingerson. Excerpt from "Report of the Committee on Structural
Petrology," Division of Geology and Geography, National Research Council, Octo-
ber, 1938, pp. 23-31.

This is the paper in which the fundamental concepts of petrofabrics were first
published. The chief one of these is that during deformation rocks undergo a
pervasive differential movement and that the deformation of the mass as a whole
is the integration of the differential displacements along s-planes. These move-
ments determine the rock fabric including even the orientation of the individual
component mineral grains, so that the symmetry of the deforming movement is
reflected in the symmetry of the fabric. Rocks that have undergone such pervasive
differential movement are called tectonites; other rocks are non-tectonites.

Another important principle is that the original fabric of a rock determines
in large measure what fabric will be impressed upon it by a given deformation.
The renewed use of existing structure planes is operative in almost any deforma-
tion from microscopic structures to the largest tectonic features. Microscopic folds
may guide later folding. Schistosity may be copied after an older structure (e.g.
bedding), or it may be thought of as an inhomogeneity that is a pattern of the
mechanical strain in the rock.

Several examples of folding are given and one is described in detail, with a
diagram to show the relation of the quartz orientation to folding, and to the
original structure of the rock.

True phyllites, produced by facsimile crystallization in an original s-plane, are
contrasted with phyllonites, which are due to the working out of a set of s-planes
to phyllitic completeness by differential motion in s.

128 CARNEGIE INSTITUTION OF WASHINGTON

A value of fabric studies is that they may be able to reveal the arrangement and
magnitude of differential movements where stratigraphic criteria fail. In many
rocks the horizons of movement can be established more surely than stratigraphic
horizons.

(963) Surface-manifestations of volcanic activity. E. G. Zies. Trans. Amer. Geophys.

Union, 19th annual meeting, pp. 10-23 (1938).

The salient features that characterize the forcible extrusion during volcanic
activity of hot gases, fluids, and solids are discussed in this paper. Typical
volcanic areas in Alaska, Central America, Java, and Bali are described and illus-
trated. Emphasis is placed on the desirability of studying more intensively than
heretofore the fumarolic activity that frequently precedes a volcanic eruption.
Attention is also directed to the fact that study restricted to surface-manifestations
can hardly yield a satisfactory explanation of the causes of volcanic activity since
an eruption is only the culmination of a long sequence of events that took place
within the hearth of the volcano.

(964) High temperature and pressure phase-equilibria in the albite — water and ortho-

clase — water systems. Roy W. Goranson. Trans. Amer. Geophys. Union, 19th
annual meeting, pp. 271-273 (1938).

Freezing-point curves in the three dimensional temperature-pressure-concentration
space are given for the albite — water and orthoclase — water systems. The
increase in solubility of water in the silicate melt with pressure lowers the
freezing point, at first very rapidly but with diminishing effect as the pressure
rises. The freezing-point curve may even have a minimum temperature above
which pressure it would begin to rise in temperature. This rapid change in
slope of the freezing-point curve between one and 2000 bars pressure is, in large
measure, a result of the effect of pressure on the solubility of water in the silicate
melt, as may be observed from the temperature-concentration projection of the
freezing-point curve.

A maximum in pressure on the freezing-point curves does not exist for any of the
rock-forming silicates investigated, and therefore pressures developed as a result
of crystallization may become relatively enormous, perhaps exceeding 5000 bars.

(965) Some recent developments and applications of the Raman effect. James H. Hibben.

Publ. Amer. Assoc. Adv. Sci., Symposium No. 7 on "Recent advances in chemical
physics" (1938).

This paper outlines the most recent work carried out at the Geophysical Labora-
tory on the application of Raman spectra to chemical and physical problems and
some typical examples of the results obtained elsewhere. In the field of inorganic
chemistry the constitution of water and aqueous solutions is discussed. The spectral
results show that water is not represented by the simple formula, H20, but has
what may be termed a continuing structure throughout the liquid. This is demon-
strable by the Raman lines which correspond to intermolecular vibrations and
hindered rotation of the water molecules. This structure is affected by temperature
and solutes. The homopolarity and ionization of inorganic compounds such as zinc
chloride in solution, and the complete ionization of the more heteropolar magnesium
chloride can be shown by the Raman spectra of these substances. The repression
of ionization in some compounds by means of a common ion effect is likewise
demonstrable.

The results obtained with sulphuric acid and fuming sulphuric acid (Chedin and
Gopala Pai) indicate that the constitution of sulphuric acid is strongly modified by
dilution and that sulphuric acid reacts with sulphur trioxide to produce pyrosulphuric
acid. Nitric acid likewise changes its constitution from the ester form HON02,

GEOPHYSICAL LABORATORY 129

on dilution, to a nitrate ion having a plane triangular configuration with the D3h

symmetry. When it is mixed with sulphur trioxide the nitric acid is dehydrated and

nitrogen pentoxide is formed.

In the field of organic chemistry it is shown that there is a strong tendency toward

hydrogen bonding with dicarboxylic acids and short-chained monocarboxylic acids.

This accounts for the peculiar behavior of the carboxyl groups in these acids.

Of particular interest to biochemistry is the unequivocal demonstration of the

zwitter-ion theory of amino acids (Edsall). When a nitrogen atom is positively

+
charged the Raman shifts corresponding to the N-H linkage differs from the

ordinary N-H ones. This observation, together with the change in carbonyl fre-
quency when the hydrogen of the carboxyl group is ionized, indicates that an

+
amino acid undergoes the following transformation: H2N-R-COOH-»H3N-R-COO~.

+
In the presence of an acid the formula is : H3N-R-COOH and on neutralization with

a base it becomes: H2N-R-COO~.

(966) The freezing-point — solubility curves of hydrates and other compounds under pres-

sure. Leason H. Adams. Amer. Jour. Sci., vol. 35A, pp. 1-18 (1938).

For the determination of equilibrium in systems under high pressure there are
two principal modes of attack. We may either devise an experimental method for
measuring directly the solubility at the various pressures, or determine indirectly the
variation of concentration with pressure under conditions of equilibrium by measur-
ing the compressibilities of the several phases and applying a simple thermodynamic
relation. In a previous communication from this Laboratory it was shown that in
the study of simple systems under pressures of several thousand bars (metric atmos-
pheres) the indirect thermodynamic method is convenient and precise. Equilibrium
curves for systems in which hydrates and other compounds appear are now consid-
ered in detail and the various equations used in passing from volume-change meas-
urements to points on the freezing-point — solubility curves are set forth, and concrete
examples are given.

(967) Lavas of the African Rift Valleys and their tectonic setting. Norman L. Bowen.

Amer. Jour. Sci., vol. 35A, pp. 19-33 (1938).

The state of knowledge and opinion as to the African Rift Valleys and their
lavas was, a decade ago, such as to suggest that a definite correlation might be
made between the tectonics and the chemistry of the lavas. The Western Rift
Valley seemed to have been formed as a result of compressive stresses in the crust
and to have associated with it lavas of potash-rich character. The Eastern Rift
Valley seemed to have been formed as a result of tensional stresses and to have asso-
ciated with it lavas of soda-rich character. The picture now presented is less simple.
As a result of further investigation there has arisen much diversity of opinion as to
the tectonic forces controlling the formation of both Rift Valleys, and there seems
therefore no adequate basis for an attempt to correlate lava chemistry with con-
trasted tectonics. In addition, recent studies of the lavas have brought to light
many exceptions to the general tendency towards preponderance of potash in the
Western Rift and preponderance of soda in the Eastern Rift. Some new analyses
are given which illustrate these exceptions and emphasize the fact that, as in the
case of the tectonic relations, no simple picture of the chemistry of the lavas can
be outlined at the present time. Indeed, when the question of the origin of the
dominant lavas of the Western Rift is reviewed in the light of latest knowledge,
their potash-rich character seems to be a relatively accidental circumstance. This

130 CARNEGIE INSTITUTION OF WASHINGTON

question is discussed and the lack of any convincing relation between lava chemistry
and tectony in the Rift Valleys is emphasized.

(968) The phenomena of Falling Mountain. Clarence N. Fenner. Amer. Jour. Sci., vol.

35A, pp. 35-48 (1938).

As a result of the eruptive activity in the Katmai region, Alaska, a large slice of a
mountain was broken loose and collapsed into the valley. For many years afterward,
the fractured scarp was the site of fumarolic activity. During the same period,
boulders and masses of rock continued to be set free and drop off.

Prior to these events, the rock of the mountain appears to have been a rather
siliceous, dense andesite, of normal appearance. The rocks that subsequently became
loosened, and formed a talus, show interesting modifications. They have been pene-
trated with irregular channels of solution, and large quantities of tridymite have
been deposited, together with cristobalite and hematite. Much mineral matter has
been carried away. The close interrelationship of the various phenomena indicates
that the removal of mineral matter, by which channels were formed, and the
deposition of new minerals, were direct results of the action of the fumarolic vapors.

(969) On the effect of pressure on the solubility of solids in liquids. R. E. Gibson. Amer.

Jour. Sci., vol. 35A, pp. 49-69 (1938).

From an empirical analysis of the data concerning the effect of pressure on the
solubility of solids in liquids, the volume changes and compressibilities of solutions,
it is concluded that only in somewhat exceptional cases is the solubility of a solid
in a liquid raised by pressure, a conclusion which is not novel. However, solutions
of the carbonates, sulphates, sulphides, fluorides, and hydroxides of some alkalis, the
alkaline earths, and the heavy metals in water, especially where the saturated solu-
tions are very dilute, are definitely to be classed among these exceptional cases,
and it is pointed out that the solubilities of these substances may be very signifi-
cantly increased by pressures below 1000 atmospheres. It seems unlikely that the
solubility of silicate minerals in molten silicates will be increased by pressure, and,
indeed, the opposite effect is more to be expected, although the complications intro-
duced by structural effects in these liquids render general statements quite risky.

The empirical arguments leading to these conclusions are given in some detail and
especial emphasis is laid on the volume change which takes place when the liquid
components are mixed, a quantity which at low pressures plays an important role
in determining the piezo-chemical behavior of polycomponent systems and some-
times renders deductions based solely on the thermodynamic behavior of the pure
components inapplicable to solutions. The effect of pressure on the solubility of
solids is correlated qualitatively with the types of cohesive forces in the pure com-
ponents and the solutions involved.

New data on the solubility of cesium bromide in water at pressures up to 1500
atmospheres and the partial volumes of sodium chlorides at 1 and 1000 bars pressure
and at temperatures between 25 and 95° C. are also included.

(970) Silicate — water systems: Phase equilibria in the NaAlSi308 (albite) — H20 and

KAlSi308 (orthoclase) — H20 systems at high temperatures and pressures. Roy W.
Goranson. Amer. Jour. Sci., vol. 35A, pp. 71-91 (1938).

This paper includes experimentally determined phase equilibrium relations for
the albite — water and orthoclase — water systems from 800 to 1200° C. and pressures
to 4000 bars and is a part of the series constituting a program of research on silicate —
water systems begun some years ago by the writer.

The freezing-point curves of these systems extend out into three-dimensional
temperature-pressure-concentration space and have been completed for albite — water.

GEOPHYSICAL LABORATORY 131

The orthoclase — water system is somewhat more complex in that at low pressures,
i.e. to about 2600 bars, orthoclase melts incongruently to leucite and liquid. The
solubility of water in this liquid has not yet been determined as a function of tem-
perature and pressure so that only the projection of the freezing-point curve on the
temperature-pressure coordinate plane is given herein for the latter system.

In order to obtain other thermodynamic data such as apparent volumes and heats
of evaporation it was necessary to obtain the temperature-pressure-volume relations
of water in this region. These latter data are in large part extrapolated, consequently
the derived thermodynamic quantities will have a lower degree of accuracy.

The data show that the pressures developed on crystallization may not only
comply with but actually exceed the pressures necessary to explain certain volcanic
phenomena.

(971) The system, Na2O.Al203.2Si02 (nephelite, carnegieite)— Na2O.Al803.6SiOs (albite).

J. W. Greig and Tom. F. W. Barth, Amer. Jour. Sci., vol. 35A, pp. 93-112 (1938).

This paper presents the results of an experimental investigation of phase equi-
librium relationships in the system, Na2O.Al203.2Si02 (nephelite, carnegieite) —
Na2O.Al203.6Si02 (albite), at atmospheric pressure, over a range of temperature
of about 500° C, within which all the melting phenomena occur. The results are
summarized and shown graphically in an equilibrium diagram, and the principal
data, on which the diagram is based, are collected in tabular form. The relationships
in this system, with albite as one end member, are similar to those found in the
corresponding system, in which the place of albite is taken by anorthite, the other
end member of the plagioclase series (N. L. Bowen, Amer. Jour. Sci., vol. 33, pp.
551-573, 1912).

In view of the similarity of these two systems it is to be expected that closely
similar relationships will be found to obtain between nephelite, carnegieite, and
feldspar across the ternary system, nephelite, carnegieite — albite — anorthite, modified
of course by the more complex nature of equilibrium in the ternary system. With
the three binary systems known (N. L. Bowen, op. tit.; Amer. Jour. Sci., vol. 35,
pp. 577-599, 1913), and no intermediate compounds except jadeite known or to be
expected, it is a simple matter to draw up a ternary diagram that, while not correct
in detail, will show the general relationships. For the convenience of the reader
such a diagram has been added.

Jadeites approach in composition the compound Na2O.Al203.4Si02 intermediate
between the two end members of this system, but jadeites are not stable at the pres-
sure and temperatures of the experiments so the compound does not appear on
the equilibrium diagram. This is consistent with the conclusion arrived at by
petrologists, from a study of natural occurrences, that jadeite is a high-pressure
phase.

(972) The constitution of some boric oxide compounds. James H. Hibben. Amer. Jour.

Sci., vol. 35A pp. 113-125 (1938).

The constitution of boric acid and its salts was investigated in detail. From
the Raman spectrum of boric acid it is concluded that this substance may be
represented by a molecule of the general type AB3 having the symmetry D3h in
which all the OH groups lie at the corner of a plane triangle with the boron atom
in the center. There are probably some intermolecular binding forces. All the
hydrogens are attached directly to oxygen atoms. Typical O-H Raman shifts
are found in crystalline boric acid.

The B02 ion from sodium metaborate is found to possess a bent structure prob-
ably having the symmetry C2v. The sodium salts of boric acid were found to yield,
on solution, mixtures of sodium metaborate and boric acid. A stepwise neutraliza-

132 CARNEGIE INSTITUTION OF WASHINGTON

tion of boric acid with sodium hydroxide results in the immediate formation of
the metaborate ion. The addition of a molal excess of hydrochloric acid to an
aqueous solution made up of water and sodium tetraborate, Na2B407, results in
a complete conversion of the tetraborate to boric acid. All these changes are
demonstrable by means of the Raman effect without altering in any way the solutions
or their constituents.

The spectrum of crystalline sodium tetraborate is consistent with the view that
the crystals are made up of long chains of boric oxide groups. The simplicity of the
spectrum makes it seem doubtful that the crystalline tetraborate consists of ring
compounds. The spectrum from borax glass is likewise simple, and it indicates the
formation of the glass by the interlacing of B03 and B02 groups. The spectrum
obtainable from a solution of the tetraborate does not differ widely from that of the
crystalline compound.

The water of crystallization in the metaborate and tetraborate yields a number
of fairly sharp water bands. There is one particularly strong and sharp O-H line
in the tetrahydrate of the tetraborate.

(973) Albite trends in some rocks of the Piedmont. Earl Ingerson. Amer. Jour. Sci.,

vol. 35A, pp. 127-141 (1938).

There are albite porphyroblasts in most of the rocks of the Piedmont province
of southern Pennsylvania and northern Maryland. Many of these albite metacrysts
show "trends," that is, they have inclusions that show pronounced alignments.
These trends have been interpreted as relict structures indicative of older periods
of metamorphism. The present work shows that the albite trends in the Port
Deposit granodiorite complex and associated rocks are not relict structures but are
controlled by the lattice of the feldspar grains. They were probably developed by
late hydrothermal activity. This does not mean that there has been only one
period of metamorphism affecting these rocks, but merely that the albite trends
cannot be used as evidence for other periods of metamorphism. Similar studies
from the literature are cited. In some of these, the trends appear to be true relict
structures. In others, they are related solely to the lattice of the host feldspars.

(974) The system, water — boron oxide. F. C. Kracek, G. W. Morey, and H. E. Merwin.

Amer. Jour. Sci., vol. 35A, pp. 143-171 (1938).

The equilibrium diagram for the system of water and boron oxide has been
established by measuring the solubility over the whole range of compositions.

The crystalline phases which occur in the system are ice, H3B03, three modifica-
tions of HB02, which are monotropically related to each other, and crystalline
B203. Solubility relations have been determined for each of these phases.

The solubility curve for ice extends only from the melting point of ice to the
cryohydric point at —0.76° C. The curve for H3B03 rises smoothly from this
point to a maximum at the melting point (metastable) of H3B03, 170.9° C. and
then descends to end at the metastable eutectic for HB02HI and H3B03.

The three forms of HB02 melt congruently: HB02I, the stable modification, at
236° C, and HB02II and HB02III,both metastable, at 200.9° C. and 176.0° C, respec-
tively. Their solubility curves have flat maxima at the composition HB02. The curve
for the stable form, HB02I, intersects the curve for H3B03 at 169° C, at which
point H3B03 decomposes to form HB02I and a solution of the equilibrium com-
position. The reaction is an abnormally sluggish one, so that the metastable con-
tinuation of the solubility curve of H3B03 is realized as if HB02I did not exist.
The curves for HB02II and HB02III intersect that of H3B03 at metastable eutectics
located at 169.6° C. and 158.5° C, in the order given.

GEOPHYSICAL LABORATORY 133

Crystalline B203 melts at 450 ± 2° C. It has been crystallized from solution in
sealed tubes, as well as in open vessels at atmospheric pressure, and various factors in-
fluencing its spontaneous growth have been established. The solubility curve for
B203 extends from the melting point to the intersection with the curve of HB02I
at 235° C, and with that of HB02II at 200° C. Both of these points are eutectics,
the second being metastable. From the slope of the solubility curve the latent
heat of fusion of B203 is calculated to be 97 cal./g.

P-T-X relations for the saturated solutions have been evaluated by combining the
solubility data with deductions based on existing vapor pressure measurements.
The resulting diagram, described in the text, brings out, among other things, the
interesting fact that crystalline B203 can coexist with solutions at a vapor pressure
of about 3 atmospheres in the neighborhood of 280° C. The oxide crystallizes rela-
tively rapidly in sealed tubes in this region of temperature. The oxide crystallizes
exceedingly slowly, on the other hand, from the nearly anhydrous melts of vitreous
B2Os, and never spontaneously in this region of composition. The spontaneous
crystallization is initiated, in the more aqueous solutions, by the presence of HB02I,
but not by the presence of the other modifications of metaboric acid.

The crystallographic and optical properties of the new crystal phases were meas-
ured, and are described in detail in the text.

(975) The unit cell and space-group of (3-glycine. C. J. Ksanda and G. Tunell. Amer.

Jour. Sci., vol. 35A, pp. 173-178 (1938).

Faceted crystals of |3-glycine the identity of which was verified under the petro-
graphic microscope by the immersion method were investigated by the equi-inclina-
tion Weissenberg method. The unit cell dimensions were found to be a0 = 5.07 A,
b0 = 6.32 A, c0 = 5.37 A, all ± 0.01 A, p = 113° 27' ± 15'. From the systematically
missing spectra P-glycine crystallizes either in the space-group C2h2 — P21/m or
in the space-group C22 — P22.

(976) Clays and other minerals from the deep sea, hot springs, and weathered rocks. H. E.

Merwin and E. Posnjak. Amer. Jour. Sci., vol. 35A, pp. 179-184 (1938).

X-rays and optical methods were used. Comparison materials, especially clays,
required study. It was found desirable in the nomenclature of the optical properties
of clays to take account of the differences in refractive index observed for some
clays when immersed in different liquids. Staining was used to indicate the presence
and the character of clays.

Some of the minerals observed in the bottom samples taken by the Carnegie were :
dolomite, considered syngenetic; muscovite, considered residual; montmorillonite
and phillipsite, syngenetic; and one unidentified iron-manganese mineral.

(977) Studies of solubility in systems containing alkali and water: I. General introduction.

II. A filter autoclave for solubility measurements at elevated temperatures and
atmospheric pressure. III. Solubility of NaOH in a saturated Na2C03 solution
between 60 and 70° C. George W. Morey and John S. Burlew. Amer. Jour. Sci.,
vol. 35A, pp. 185-215 (1938).

The application of physico-chemical principles to the problems of pegmatite forma-
tion and the hydrothermal alteration of minerals requires knowledge of the solubility
or fusion surface of the system, Na20 — K20 — A1203 — Si02 — H20, at temperatures
below about 600° C. As a first step toward gaining this knowledge a new type of
autoclave has been designed for solubility studies by the analytical method. With
it a mixture of solid and liquid at a constant temperature can be stirred in a silver
vessel and then filtered through a platinum felt, after which the filtrate is cooled and
analyzed. Such an autoclave for use at atmospheric pressure has been perfected
during investigation of part of the system, NaOH — Na2C03 — H20, at elevated

134 CARNEGIE INSTITUTION OF WASHINGTON

temperatures. The liquidus temperatures along the boundary curves NaOH.H20 —
Na2C03 and NaOH — Na2C03 between 60 and 70° are now reported, together with
the optical properties of NaOH.H20 and NaOH.

(978) The system, water — sodium disilicate. G. W. Morey and Earl Ingerson. Amer.

Jour. Sci., vol. 35A, pp. 217-225 (1938).

An apparatus has been constructed for studying the lowering of melting point of
silicates when heated in steam at high pressures, and the results of a study of the
system, water — sodium disilicate, are presented.

(979) Radium in rocks. V: The radium content of the four groups of pre-Cambrian granites

of Finland. Charles Snowden Piggot. Amer. Jour. Sci., vol. 35A, pp. 227-229
(1938).

The radium content of the pre-Cambrian granites of Finland is reported, grouped
according to the four classifications of Sederholm.

(980) Radium and the petrology of certain granites of Finland. Tom. F. W. Barth. Amer.

Jour. Sci., vol. 35A, pp. 231-245 (1938).

The radium content of various types of granites of Finland is compared with
certain petrologic characteristics of the several rocks. No relation is found
between radium and potash or ferrous oxide, but for granites belonging to the
same type the radium content can be correlated with the amount of biotite.

(981) The system, CaS04 — H20. E. Posnjak. Amer. Jour. Sci., vol. 35A (1938).

Since the appearance many years ago of the investigation by van't Hoff and his
associates on the various calcium sulphates and their relationships, which formed
part of their classical work on the formation of the Stassfurt salt deposits, there has
been an unending controversy regarding the true state of affairs in the system,
CaS04 — H20. No attempt, however, is made to give a detailed review of this litera-
ture. After considering the facts which have been brought out, and checking experi-
mentally some that seemed most pertinent, the present investigation found that the
basis for most disagreements was some erroneous suppositions regarding phase rela-
tions involving hydrated compounds. These misled van't Hoff et al. to assume
that a dissociation reaction took place when they found that under certain condi-
tions anhydrite, and, as they thought, "soluble anhydrite" also, had crystallized in
solutions at the expense of gypsum. As a result of this and the sluggishness of
reaction in the case of the formation of hemihydrate, their data are erroneous.

Data brought out by various investigators, which are recounted in the text, fur-
nish definite and reliable information regarding the system, CaS04 — H20, between
0 and 200°. The transition point, gypsum — anhydrite, lies at 42 ± 1°, and that of
gypsum — hemihydrate at 97 ± 1°. In the region between these two temperatures,
gypsum is truly metastable. The transition point for hemihydrate into "soluble
anhydrite" (y-CaSOJ lies apparently at a high temperature, and, owing to the in-
stability of the two phases, cannot be established. A monotropic relation exists
between anhydrite (P-CaS04) and "soluble anhydrite" (Y-CaS04).

Regarding the geologically important question of the conditions under which
anhydrite may be deposited at ordinary temperatures, available information indicates
that a high concentration of salt solutions is not required, but that anhydrite may
be deposited from relatively dilute solutions.

(982) Direct measurement of silicate heats of melting. Howard S. Roberts. Amer. Jour.

Sci., vol. 35A (1938).

The reluctance of most silicates to crystallize when once melted makes it difficult
to obtain their heats of melting when using calorimeters operated at room tempera-

GEOPHYSICAL LABORATORY 135

tures. It is here shown that with a suitable high-temperature calorimeter we may
measure the energy actually absorbed by the silicate in the act of melting, as is often
done at low temperatures, and so obtain data of usable precision. Determinations
are described using pure K2S04 and somewhat impure Na2Si03 whose melting points
are 1069° and 1089° respectively.

(983) The system, leucite — diopside — silica. J. F. Schairer and N. L. Bowen. Amer. Jour.

Sci., vol. 35A (1938).

Several silicate systems have been investigated or are now being studied to ascer-
tain what compositions residual liquids from fractional crystallization approach.
This system combines the simple pyroxene, diopside, with potash-alumina silicates.
Phase equilibrium data show that diopside is almost quantitatively removed, leaving
liquids almost free from the pyroxene molecule.

Melting data for the system, leucite — diopside — silica, are presented by means of
tables and a ternary diagram. There are no ternary compounds. There are two
ternary invariant points, one a reaction point and the other a ternary eutectic.
The field of diopside occupies a large part of the ternary diagram, and with mixtures
containing even less than two per cent diopside in their total composition, diopside
appears as the primary phase. On fractional crystallization, residual liquids ap-
proach in composition a mixture of potash feldspar and silica. A diagram showing
the indices of refraction of ternary glasses is given, and also a preliminary diagram
for the binary system, leucite — silica.

(984) The gases in rocks and some related problems. E. S. Shepherd. Amer. Jour. Sci.,

vol. 35A (1938).

From the analysis of Kilauea gases collected in vacuum tubes the study was ex-
tended to those gases still retained by freshly collected lavas from Kilauea and other
volcanoes. Later the work included gases from typical plutonics obtained by ex-
hausting such rocks in vacuo. In the latter case it was found that careful selection
of the material was needful and the geological implications of "alteration" were set
forth. Studies of obsidians with varying amounts of water in solution revealed some
important physical properties due to their water content, and the relation of these
to the mechanism of lava flows in general is emphasized.

(985) Evidence on the intrusion-temperature of peridotites. Robert B. Sosman. Amer.

Jour. Sci., vol. 35A (1938).

Experiments in heating a coke inclusion from a peridotite dike in Fayette County,
Pennsylvania, and chemical analyses of the same inclusion for hydrogen, oxygen,
and nitrogen, agree in indicating that the maximum temperature reached by the
coke was between 440 and 520° C. The intrusion-temperature of the peridotite
could hardly have exceeded 600°. How a rock of peridotitic composition could
have been intruded at so low a temperature remains to be determined by laboratory
experiment.

(986) The crystallography of potassium tetrathionate. G. Tunell, H. E. Merwin, and C. J.

Ksanda. Amer. Jour. Sci., vol. 35A (1938).

Analyzed artificial crystals of potassium tetrathionate were measured on the two-
circle reflection goniometer and their geometrical constants were calculated. The
dimensions of the structural unit cell were determined by means of equi-inclination
Weissenberg photographs to be a0 = 22.05A, b0 = 7.99 A, c0 = 10.09 A, all ± 0.02A,
P = 102° 05' ± 15'. From the systematically absent spectra, the crystal habit,
and the presence of pyro-electric and piezo-electric effects, the space-group of
potassium tetrathionate is Cs4 — Cc. The refractive indices and their dispersion

136 CARNEGIE INSTITUTION OF WASHINGTON

were determined by the method of minimum deviation, and the optical orientation
was established.

(987) An improved torsion gravity meter. F. E. Wright and J. L. England. Amer. Jour.

Sci., vol. 35A (1938).

In the improved instrument, recently built at the Geophysical Laboratory, the
torsion element is the same as that used heretofore; but its other parts have been
rearranged to provide simpler control for operation in the field. The present
apparatus is lighter than its predecessor and gives promise of even better field
performance. The old instrument during its last period of eight months' service
in occupying and reoccupying old and new gravity stations yielded results that,
for any given station, agreed within one milligal. The new instrument is mounted
inside a covered insulated motor truck; under ordinary conditions twenty or more
stations per day can be occupied by the apparatus.

(988) The concentration of the less familiar elements through igneous and related activity.

E. G. Zies. Amer. Jour. Sci., vol. 35A (1938).

Reprint, with slight modifications, of No. 958.

(989) The Earth's interior: Its nature and composition. Leason H. Adams. Smithsonian

Report for 1937, pp. 255-268. Published 1938.

Reprint, with slight modifications, of No. 921 .

(990) Annual Report for 1937-1938.

DIVISION OF HISTORICAL RESEARCH1

A. V. Kidder, Chairman

The Division of Historical Research comprises three Sections. The Sec-
tion of Aboriginal American History concerns itself with studies relating to
the rise of native civilization in the New World, its two principal fields being
the Maya area in Mexico and Central America, and the Pueblo area of
southwestern United States. The Section of Post-Columbian American
History conducts research upon the growth of Western European institutions
in the Americas. The Section of the History of Science strives to bring to-
gether and to make available for interpretation the at present widely
scattered and uncoordinated data which bear upon the acquirement and
transmission of ordered knowledge.

It is the policy of the Division that no new unit of research shall be under-
taken until at least the factual results of previous activities in the field con-
cerned have been made of record. A large share of the Division's energies,
during the past year, has accordingly been devoted to the working up of
accumulated data and the writing of reports. This has served to direct
special attention to problems of publication.

In general, first class factual literature in the social sciences and the
humanities is pitifully scanty. In these, as in the natural sciences, the col-
lection and the setting forth of data must precede synthesis and the drawing
of conclusions. And because of the bewilderingly faceted life of man and
the infinitely wide range of man's doings throughout the ages, in every
conceivable type of historical setting, and in all possible sorts of physical
environments, the human record must, for the present at least, be largely
descriptive. Expression by formula is not feasible, nor can there often be
used the condensed forms appropriate for exposition of the regularly repeat-
ing phenomena of biology. Publication, therefore, even in the case of the
relatively small group of studies with which the Division is occupied, is
inevitably voluminous; archaeological papers must carry a great amount of
illustration. Costs, accordingly, are bound to be heavy; but, on the other
hand, it is only fair to point out that acquisition of most anthropological and
historical materials is relatively inexpensive, there being little or no call
for physical equipment, for laboratories or instruments. However, neither
need for much publication nor cheapness of fact finding justifies waste.
Also, from the point of view of utility, it is essential that results be thor-
oughly digested and succinctly stated.

Because of the vast increase in scientific writing of all sorts, as well as
because of the rapidly mounting costs of printing, it is certain that present
methods for dissemination of knowledge will have to be rather drastically
overhauled, those of the disciplines concerning man perhaps most severely
of all. How this may be brought about, in the case of its own product,
is being given anxious consideration by the Division. Those of its reports
which are now well along in preparation will be submitted in forms sanc-
tioned by previous practice. But it is probable that current studies of the

1 Address: Carnegie Institution of Washington, 16th and P Streets N. W., Washing-
ton, D. C.

137

138 CARNEGIE INSTITUTION OF WASHINGTON

situation will result in recommendations looking toward much simplified
presentations and considerable reduction in manufacturing costs.

SECTION OF ABORIGINAL AMERICAN HISTORY

The work of the Section in the Maya field consists of archaeological exca-
vation, exploration, and the comparative study of certain particularly im-
portant aspects of Maya culture, such as the hieroglyphs, architecture,
sculpture, and pottery. The Section also sponsors research in ethnology
and linguistics, and cooperates with other agencies in biological, geological,
and other studies designed to throw light on the environment in which the
pre-Columbian Maya developed their remarkable civilization, and in which
their descendants live today side by side with their Spanish conquerors.
Workers in the Sections of Post-Columbian American History and the His-
tory of Science, carrying forward investigations in their own fields, add to
the large body of information being accumulated in regard to the Maya.

As has already been stated, much of the time of the Division staff has,
during the period under review, been spent in making the above informa-
tion available through the writing of reports. Outstanding among several
manuscripts so brought to completion are those of Dr. Morley, who has in
press his compendious monograph on the hieroglyphic inscriptions of the
ruined Maya cities of Peten, the fruit of over twenty years of study ; and of
Mr. Morris, whose report, embodying the results of his equally long-con-
tinued investigations in the very important Basket Maker and Pueblo sites
of northern New Mexico and adjacent regions, is. ready for the printer.
These two monographs will always rank as fundamentally significant con-
tributions to the literature of their respective fields. Progress in working
up the results of other activities is noted below.

Uaxactun. Excavation at Uaxactun, in the Department of the Peten,
Guatemala, was discontinued in the spring of 1937. This apparently oldest
of First Empire Maya cities was under investigation for no less than eleven
seasons. Findings of the first years have been recorded by Dr. and Mrs.
Ricketson in a volume recently issued.1 The six years 1932-1937 were
largely devoted to study of the so-called "Palace," a multi-chambered struc-
ture which grew by accretion through a long period of time, and whose
thorough dissection by A. L. Smith yielded extremely valuable data upon
architectural development and the succession of pottery types. Mr. Smith
and E. M. Shook, his associate during most of the work on the Palace, have
been engaged, since the close of work at Uaxactun, in preparing the final
report upon the general archaeology of the site; while R. E. Smith, assisted
by Mrs. Smith, has been studying and writing up, at the Institution's labora-
tory in Guatemala City, the enormous ceramic collections made at Uaxactun.
It is believed that at least eighteen months more will be required for com-
pletion of these two papers.

Kaminal-juyu. The Chairman's excavations in the mounds and tombs
of Kaminal-juyu, near Guatemala City, were also discontinued in 1937.

1 Uaxactun, Guatemala, Group E, 1926-1931. Carnegie Inst. Wash. Pub. No. 477 (Sep-
tember 1937).

DIVISION OF HISTORICAL RESEARCH 139

The collections, particularly the pottery, throw much light upon the chrono-
logical relations between the cultures of the Guatemala highlands, those of
the Maya First Empire in Peten, and those of central Mexico. Owing to
collapse of the roofs of the tombs, the pottery accompanying the interments
was badly broken and crushed. The difficult task of repairing the more than
two hundred vessels, many of great beauty, and for the most part of types
hitherto unknown, was carried out by Mr. Paul Richard of the American
Museum of Natural History and Mrs. Harriet S. Cosgrove of the Peabody
Museum of Harvard University, whose invaluable services were most gen-
erously made available to Carnegie Institution by Dr. Clark Wissler and
Mr. Donald Scott, directors of the above museums. The skill of Mr.
Richard and Mrs. Cosgrove served to put the pottery in shape for study,
and for permanent exhibition in the National Museum of Guatemala, where
it has now been deposited. Each piece was photographed by Miss Barbara
Kidder and all outstanding pieces were reproduced in black and white or in
water color by the Section's artists, Senores Antonio Tejeda and Victor
Lucas. The Chairman spent the winter at the Guatemala laboratory, mak-
ing notes on the pottery and other artifacts and on the specimens, other than
ceramic, from Uaxactun. Mrs. Kidder, who, from the beginning of the
Kaminal-juyu operations in 1935, has cared for and catalogued the collec-
tions, made, this year, a special study of the large number of jades found
in the tombs.

Guatemala Office. In addition to routine archaeological activities, the
Guatemala Office, under direction of R. E. Smith, has continued to serve as
local headquarters for research workers and visitors from several other
institutions: Jeffries Wyman, biologist of the Museum of Comparative
Zoology at Harvard; Linton Satterthwaite and J. Alden Mason, archaeolo-
gists of the University of Pennsylvania Museum; Theodor Dobzhansky,
geneticist of the California Institute of Technology and Carnegie Institu-
tion; J. Andrews King, ornithologist of the Field Museum of Natural His-
tory; and L. C. Stuart, herpetologist of the University of Michigan. By
supplying information, making advance arrangements, securing necessary
permits, and attending to the importation of supplies and the exportation of
collections, the office is in position greatly to facilitate the work of the
scientists who come to Guatemala for special investigations. The Divi-
sion and Guatemala offices have also made available to the Shell Oil Com-
pany and the Fairchild Company all data in their possession regarding the
Department of the Peten, where those organizations are carrying on geo-
logical and air-photographic surveys, the results of which will be of much
value for the study of Maya archaeology.

Architectural survey. During the past several years, Dr. H. E. D. Pol-
lock has been engaged in architectural research in northern Yucatan, a field
so large and so rich in remains that it has seemed best to treat it by chrono-
logical and topographic units. The important area of the Puuc, containing
the most abundant and most representative ruins of the so-called "Maya
renaissance," has now been explored and Dr. Pollock has devoted as much
time as could be spared from his organization of the Section's photographic
files (see p. 140) to preparing a report upon them. It is hoped that in this

140 CARNEGIE INSTITUTION OF WASHINGTON

paper methods can be developed for a briefer and more effective presenta-
tion of architectural data than has hitherto been attained.

Archceology of British Honduras. Mr. J. E. Thompson's work at the
ruins of San Jose was begun as a joint project with Field Museum and com-
pleted by Carnegie Institution in 1936. San Jose, a small site, occupied
from before the rise of the First Empire to a period apparently only shortly
antedating the advent of Mexican influence in Yucatan, is important because
it well exemplifies the minor communities, of which great numbers existed,
and which must have formed the backbone, so to speak, of the Maya com-
monwealth, but which have hitherto largely been neglected by archaeologists
in favor of the larger, more spectacular cities. Its long occupation also
rendered it an unusually favorable place for study of ceramic development.
Mr. Thompson has divided his time during the past eighteen months be-
tween glyphic research and the study and preparation for publication of the
archaeological materials from San Jose. His report on the latter is now
in press. He also made a short field trip to British Honduras during the
winter of 1938 (see p. 152).

Geographical study. Information regarding the physical features of the
Maya area, its geology, topography, climate, is scattered through a great
number of publications: narratives of the Conquest, books of travel, scien-
tific periodicals, government reports. In order to render this indispensable
but now relatively inaccessible material available, Dr. 0. G. Ricketson, Jr.,
is making a thorough search of the literature, is preparing an annotated
bibliography, and is gathering notes for a general work upon the geography
of southern Mexico and northern Central America, suitable for the use of
the archaeologist, the ethnologist, and the historian.

Photographic files. During the quarter-century of the Institution's work
in the Maya field there have been accumulated more than 20,000 photo-
graphic negatives. These constitute the basic record of every excavation
and exploration carried out by the Section. In the early years each in-
vestigator assumed charge of the photographs dealing with his own branch
of the work. As the Maya project grew, however, it became obvious that a
central repository must be established for the safe-keeping and adequate
cataloguing of these pictures. A consolidated file was begun at the Section's
former administrative office in Washington, but not until general head-
quarters were established did it become possible to assemble all the material
and to secure from the hitherto scattered members of the staff the identifica-
tions necessary for accurate labeling.

In 1935 a new uniform system of field recording of photographs was put
into operation by Dr. Pollock and during the past two years he has brought
order into the great mass of older pictures. With the help of Miss Ritchie
his reorganization of the file is now approaching completion. Negatives,
contained in fireproof cases, are arranged serially by years ; prints, mounted
on cards and bearing negative number and identifying description, constitute
a second series in which the photographs are grouped for ready reference by
sites and subgrouped in such a way as to bring together all data upon in-
dividual buildings, stelae, pottery, etc.

DIVISION OF HISTORICAL RESEARCH 141

The foregoing activities indicate how large a proportion of the time of
the Section's staff was spent, in 1937 and 1938, in laboratory work and in
writing. In spite of this, several field projects were undertaken. Summary
accounts are appended.1

Chichen Itza — S. G. Morley

The Chichen Itza Project of the Carnegie Institution of Washington began
its fifteenth year in January. Dr. and Mrs. Morley reached Yucatan by
way of Mexico City on December 28, and Messrs. E. T. P. Kennedy, R. T.
Patton, J. H. Denison, Jr., and W. E. Shepherd (the last two, members of
the Fifth Campeche Expedition) on January 6. Mr. Karl Ruppert, Direc-
tor of the Fifth Campeche Expedition, reached Yucatan by way of Mexico
City at the end of January and the expedition left Merida for central Cam-
peche at the end of February, returning therefrom early in April.

Dr. Morley devoted the first six months of the year to correcting proof on
his coming monograph on "The Inscriptions of Peten." The galley proof
was completed and the first two volumes of page proof before he sailed for
Europe on June 28 by way of Vera Cruz to attend the sessions of the Second
International Congress of the Anthropological and Ethnological Sciences held
at Copenhagen, Denmark, from August 1 to 6. In addition to representing
the Institution at this congress he was also a member of the United States
Government delegation thereto. He presented two papers: "A Review of
Twenty-five Years' Research in the Maya Area of Middle America by the
Carnegie Institution of Washington, 1914-1938" and "The Rise and Fall of
the Maya Old Empire as Established by the Hieroglyphic Inscriptions."

The most important activity under the Chichen Itza Project during the
current year, except the Fifth Campeche Expedition described elsewhere,
was the survey of the ruins of Mayapan in northern central Yucatan, made
by Mr. R. T. Patton, the expenses of which were defrayed partly by Mr.
Patton himself, Mr. Percy Jackson, and Colonel F. Marion Barker, and
partly by the Institution.

This survey was undertaken because the archaeological importance of
Mayapan as indicated by the brief descriptions of Stephens, Brasseur de
Bourbourg, and later visitors, including several of the Institution's staff,
appeared to be far less than its political preeminence in the thirteenth, four-
teenth, and fifteenth centuries, as established by the Spanish and native
chroniclers, would have demanded. The early authorities describe the site
as walled, but although Stephens saw a section of the wall, nothing was
known of its extent.

The Institution's survey establishes that the wall surrounding Mayapan
is 5% miles in circuit, enclosing a rough oval about 2 square miles in area.
The wall is made of dry-laid, irregular blocks of limestone, not dressed, with
a very slight batter on both sides. The wall varies from 9 to 12 feet in thick-
ness at the base and from 6 to 7 feet in height outside. There was formerly
a low parapet along the outer edge of the wall, though in most places this
has now fallen. There are several stairways on the inside leading to the top.

1 See also p. 170 for a progress report upon Dr. Pogo's research in Maya astronomy, and
p. 166 for statements regarding investigations in the documentary history of the Maya area.

142 CARNEGIE INSTITUTION OF WASHINGTON

Nine entrances, irregularly distributed and ranging in width from 3 to 6 feet,
give access to the walled area. This number was of considerable importance,
being that of the gods of the nine underworlds of Maya mythology, each
one of which may have presided over one of the nine gates of the site.

The principal pyramids and mounds as well as the stelae are concentrated
near the center of the walled oval area. This central section was divided
into squares of 200 meters on a side and surveyed, all constructions being
exactly located. The principal axes of the central area were projected until
they intersected the wall, and the central area tied thereto in four places.
Finally, the 5%-mile circuit of the wall was surveyed by means of lines of
sight just inside cut through the thick bush.

The constructions consist of pyramids, platforms, colonnades with drum
columns, corbel-arched buildings, and four round towers, possibly astronomi-
cal, only one of which had been previously reported. There is little dressed
masonry, surfacing for the most part having been effected by stuccoing. The
architecture is far inferior to that of the other great cities of northern Yuca-
tan— Chichen Itza, Uxmal, and those of the Puuc and Chenes regions. It
more closely resembles that of the relatively late site of Tulum on the east
coast of Yucatan ; the latter is also the only other walled site known in the
Maya area. These several points indicate that Mayapan rose to political
preeminence at a relatively late period in Yucatan history, probably not until
the twelfth or thirteenth century.

Nineteen cenotes were found within the walled area, for all of which, ex-
cept two, native Maya names were obtained.

Eleven stelae were located, nine sculptured and two dressed but plain. At
the time Mayapan flourished Initial Series dating had been replaced through-
out the Maya area by Period Ending dating, a method which, although not
nearly so accurate as the Initial Series, served nevertheless to distinguish
one katun or 20-year period from another within a period of two and a half
centuries. Three Period Ending dates were deciphered by the writer on
Mayapan monuments: Stela 1, Katun 10 Ahau, a.d. 1185, probably
10.18.0.0.0 10 Ahau 3 Tzec; Stela 5, Katun 4 Ahau, a.d. 1244, probably
11.1.0.0.0 4 Ahau 8 Mol; Stela 6, Katun 13 Ahau, a.d. 1283, probably
11.3.0.0.0 13 Ahau 13 Pax.

The results of this survey indicate that although Mayapan reached a posi-
tion of first importance only at the close of Maya history when architectural
decadence was well under way, its size satisfactorily agrees with the political
preeminence ascribed to it by both the native and the Spanish chroniclers.

An epigraphic discovery of importance made by Mr. Alfonso Villa R. on a
trip to the highlands of Chiapas, Mexico, in connection with the Ethnological
and Sociological Survey should be mentioned here. He reports for the first
time a monument from Tila, to which the designation Stela C has been given.
This records both as an Initial Series and as a Period Ending the date
9.13.0.0.0 8 Ahau 8 Uo in bar and dot numerals.

Dr. Morris Steggerda of the Department of Genetics was at Chichen Itza
for the eighth season in connection with his anthropometric, ethnological,
and sociological studies. His experimental milpa is now entering its fifth
year, and this protracted investigation of corn cultivation as practiced by

DIVISION OF HISTORICAL RESEARCH 143

the modern Maya is proving one of the most fundamental studies made by
the Institution in the Maya field.

As usual the Institution's headquarters at Chichen Itza were again utilized
by investigators of other organizations. M. Andre Remondet, winner of
the Grand Prix de Rome in 1937, having elected Maya architecture as his
field for special study, spent three months at Chichen Itza in the winter
and early spring making measured drawings, ground plans, and elevations of
some of the more important buildings: the Castillo, the Mercado, the Vapor
Bath, and the Temple of the Three Lintels. These drawings together with
a wash drawing of the last were exhibited in the French Academy at Rome
during May.

During June Dr. and Mrs. C. L. Lundell of the Herbarium of the Uni-
versity of Michigan were at Chichen Itza collecting botanical specimens in
connection with the former's study of the botany of the Yucatan Peninsula.
In July they spent three weeks collecting at Coba in northeastern Yucatan,
using the Institution's camp equipment from Chichen Itza and taking with
them as assistants several Maya from the neighboring village of Piste, who
have been working for the Institution in Yucatan during the past fifteen
field seasons. The month of August was devoted to collecting in the north-
western part of Yucatan near Merida and the ecologically important north-
west coast region.

The 1938 Botanical Expedition to Yucatan and Quintana Roo,

Mexico — C. L. Lundell

In continuation of the biological survey of the Maya area, under the
joint auspices of the University of Michigan and the Carnegie Institution
of Washington, botanical investigations were undertaken in Yucatan and
Quintana Roo, Mexico, from May 27 through August 3, 1938, by the writer,
and Amelia A. Lundell, who served as field assistant. The expedition,
supported by the Horace H. Rackham School of Graduate Studies, and
the Faculty Research Fund, University of Michigan, carried out intensive
explorations in the coastal area forty miles east and west of Progreso, around
Chichen Itza for a radius of twenty miles, and in the vicinity of Coba, Quin-
tana Roo. Important but smaller collections were made along the road
south to Uxmal and around Merida. Facilities of the Carnegie Institution
of Washington at Chichen Itza, generously placed at the disposal of the
expedition, contributed substantially to the success of the field work.

The State of Yucatan has been worked more extensively by resident col-
lectors and visiting botanists than any other part of the Yucatan Peninsula,
yet few data have been gathered concerning such important subjects as the
general aspects of the vegetation, zonation, abundance and distribution of
species, successional stages, relic forest areas and their importance in the
interpretation of the natural climatic climax forest. Biotic influences, which
include the effect of milpa agriculture and fire destruction, have been largely
ignored. Hence these subjects were given primary consideration. In the
course of the studies, approximately 8000 herbarium specimens were col-
lected, included among which are adequate series of such difficult groups

144 CARNEGIE INSTITUTION OF WASHINGTON

as cacti and palms. Many of the described endemics, some known from
single collections without locality data, were rediscovered and gathered re-
peatedly with both flowers and fruits. A few species, some characteristic of
the Yucatan and Quintana Roo forests, appear to be new to science. Clearer
taxonomic interpretation of a number of species and some genera, hereto-
fore inadequately known, will now be possible from the ample herbarium
material obtained. To substantiate and amplify ethnobotanical data, this
subject received special attention in the Chichen Itza area with the able
assistance of Mr. Francisco Campos, who served as our interrogator of
Maya herb doctors and farmers. The extensive collections from Coba, the
first large series from the interior of Quintana Roo, reveal an astonishingly
close floristic and physiognomic relationship between the east coast forest and
the older forest of Yucatan. Collections of reptiles and amphibians from
Chichen Itza and Coba, and fish from Lake Coba and Lake Macanxoc,
Quintana Roo, were made incidentally to the botanical work.

It is premature to describe the vegetation of Yucatan and Quintana Roo
before the collections have been identified and the extensive field notes
critically analyzed, hence the following preliminary discussions should be
considered tentative and subject to revision.

The dry coastal area, east and west of Progreso, consists of three distinct
physiographic zones: (1) the sand dunes lying between the sea and the
cienaga; (2) the shallow cienaga and salt flats; and (3) the limestone flats
extending for about ten miles south from the edge of the cienaga into the
interior.

The sand dunes, in areas remote from the coastal settlements, support
low thickets ranging up to 15 feet in height. Around Progreso and other
villages, cutting for wood, charcoal, and other needs keeps the vegetation
down so that it scarcely exceeds 5 feet even in the most favorable spots. The
abundant treelets and shrubs of the dunes include species in the following
genera: Metopium, Coccoloba, Thrinax, Coccothrinax, Hippocratea, May-
tenus, Bumelia, Capparis, Lycium, Agave, Jacquinia, Rhacoma, Thevetia,
Ccesalpinia, Cordia, Tournefortia, and Gymnopodium. Cacti are locally
abundant, but nowhere as common as in the area south of the cienaga. Of
particular interest is the occurrence on the sand dunes, as shrubs or gnarled
treelets, of such species as Achras Zapota, Krugiodendron ferreum, Thevetia
peruviana, and Metopium Brownei, all of which are large trees in the wet
forest to the south.

The cienaga, a shallow salt-water swamp behind the dunes, has wide areas
of open water with islands of mangrove. The bordering flats usually are
covered with mangrove, or in open areas with Salicornia, Batis, and other
halophytic herbs.

From the southern edge of the cienaga low limestone flats, interspersed with
rainy-season ponds, have a distinctive vegetation which extends inland for
approximately ten miles in the Progreso region. Because of the high per-
centage of endemics and the predominance of cacti, this xerophytic belt,
where rainfall does not exceed 20 inches, is one of the most interesting phyto-
geographical areas in the peninsula. The vegetation reaches a height of 45
feet in undisturbed sections, but averages much less in the proximity of vil-

DIVISION OF HISTORICAL RESEARCH 145

lages owing to culling and clearing. The large cacti, Nopalea Gaumeri, N.
inaperta, Pachycereus Gaumeri, Lemaireocereus griseus, and Cephalocereus
Gaumeri, are abundant, forming almost impenetrable thickets in undisturbed
sections. Low cacti, Opuntia Dillenii, Acanthocereus pentagonus, and sev-
eral other species, not identified, are locally conspicuous. The interesting
low species of Neomammillaria abound here only. Species in the following
genera are the principal associates of the cacti : Acacia, Mimosa, Pedilanthus,
Agave, Hcematoxylum, Euphorbia, Prosopis, Zanthoxylum, Pithecolobium,
and Croton.

Inland from the cactus thicket zone, the limestone plain rises slightly, ex-
tending unbroken southward to the low sierras bordering Yucatan on the south
and southwest. With increase of rainfall from the coast inland, the vegetation
undergoes a marked transition, although this transition is masked by in-
vasion of species from the dry cactus zone, a result of biotic disturbances.
The greater part of the State of Yucatan, not planted in henequen or cleared
for milpas, is covered with low thickets from 10 to 25 feet in height. These
are all second growth, the result of repeated clearing and fire destruction.
Two species of legumes, Acacia Gaumeri and Mimosa hemiendyta, both native
to the peninsula, are the principal dominants, with a host of shrubs and
vines as associates. This widespread assemblage, often considered to be
the typical vegetation of Yucatan, is nothing more than an early successional
stage.

In a country which has supported as large an Indian population as Yuca-
tan, thinly settled outlying districts are likely to contain the only sections
of forest little disturbed by man. In the search for data with which to re-
construct the appearance of the old climax vegetation of Yucatan, border-
line country, far from villages and outside the limits usually reached by
milperos, was combed. Here stands of advanced forest, with relics of
Achras Zapota and other slow-growing hardwoods, were discovered.

The floristic composition and physiognomy of the advanced and relic
forest stand out in marked contrast against the widespread young legume
thickets. The height usually exceeds 50 feet. Species rare in the young
thickets are here abundant, whereas Acacia Gaumeri, Mimosa hemiendyta,
and other associates of the low rank growth are comparatively rare. Princi-
pal trees of the advanced and relic hardwood forest include the following:
Lysiloma bahamense, Vitex Gaumeri, Metopium Brownei, Piscidia sp.,
Swartzia sp., Lonchocarpus spp., Achras Zapota, Coccoloba spp., Bursera
Simaruba, Ccesalpinia spp., Thouinia paucidentata, Torrubia sp., Hippo-
cratea sp., Albizzia sp., Guettarda Combsii, Byrsonima bucidcefolia, and
Malmea sp. Of the tall shrubs, the following are abundant: Gymnopodium
sp., Neomillspaughia sp., Diospyros spp., Eugenia spp., Acalypha spp.,
Croton spp., Hampea trilobata, Randia spp., Erythroxylon spp., and Bau-
hinia spp.

The most extensive remnants of the old forest were found in the vicinity
of Yokdzonoot between the villages of Piste and Libre Union, and along
the road from Chichen Itza to Kaua. Scattered stands of old second growth
along the road from Merida to Uxmal have much the same assemblage of
species. The relic forest east of Coba, Quintana Roo likewise resembles

146 CARNEGIE INSTITUTION OF WASHINGTON

the advanced forest near Yokdzonoot and along the Kaua road; in fact,
the stands at Coba differ little floristically, and the dominants are the same.
We may conclude that similar forest probably extended at one time as a
wide belt across the northern tip of the peninsula, possibly as far south as
Peto and Champoton. Its southern extension along the east coast is not
known.

Throughout this zone, endemics outnumber in individuals all other species,
therefore comprise the bulk of the forest mass. In 1936 a similar condition
was observed in advanced forest on the limestone plateau of southern British
Honduras.

The older forest of Yucatan, deciduous with few exceptions during the
dry season, may be designated as advanced deciduous forest to distinguish
it from the advanced, predominantly evergreen quasi-rain forest of southern
Campeche, southern Quintana Roo, northern Peten, and northern British
Honduras.

This advanced forest of Yucatan and northern Quintana Roo differs
considerably in dominance and to a certain degree floristically from the
southern quasi-rain forest. Of significance is the absence in the north of
such typical southern species as the escoba palm, Cryosophila argentea.
The distribution of species in such genera as Gymnopodium, N 'eomillspaughia,
Diospyros, Cryosophila, Acacia, Mimosa, Orbignya, and Swietenia must
be studied to obtain satisfactory data by which these two phytogeographical
areas may be more accurately delimited.

In spite of the fact that the relic forest east of Coba differs considerably
from advanced forest in the vicinity of Old Empire ruins in southern Cam-
peche and northern Peten, the forest covering the ruins of Coba compares
very favorably with forest covering such sites as Calakmul, Topoxte, Naach-
tun, and Yaxha. On the Coba ruins, Brosimum Alicastrum dominates, with
the following associates much in evidence: Achras Zapota, Cedrela mexi-
cana, Talisia olivceformis, Sabal sp., Protium Copal, Thevetia peruviana, and
Chlorophora tinctoria. All these are important in the economy of the
Maya. Of interest is the prominence of Chlorophora tinctoria and Thevetia
peruviana, both of which occur as trees up to 10 and 16 inches respectively
in diameter. Neither one has been observed on Old Empire sites heretofore.
An orange grove of undetermined age was discovered in a plaza growing in
the shade of high ramon forest. Could this grove be a relic from Conquest
times?

The role of fire in the destruction of tropical forest is nowhere more evi-
dent than in areas of Quintana Roo visited. Beyond the village of Dzitnup,
along the trail to Coba, we rode for four hours through utterly desolated
country. For at least six years, possibly longer, annual dry-season fires
have swept through. In some places a few scattered large relic trees, Vitex
Gaumeri, Metopium Brownei, and Piscidia sp., all noted for their fire re-
sistance, still stand, which indicates that high forest covered the area pre-
viously, a fact attested to by Indians in Dzitnup. In some sections, not a
living plant remained from the former forest, only fallen trees and standing
skeletons. Not only has the forest been killed, but the destruction of the
humus and roots by fire has resulted in complete erosion of the thin mantle

DIVISION OF HISTORICAL RESEARCH 147

of soil into underground crevices to leave barren stretches of white pitted
limestone.

Approaching the ruins of Coba, a section has escaped the fires for possibly
two years. Here the rank second growth consists mainly of cecropias,
acalyphas, and morning glory vines. East of Coba, fire destruction has
not been as severe; the forest there, as already pointed out, resembles
remnants of old Yucatan forest. The area of fire-culled forest is said by
chicleros to extend unbroken almost to Tancah on the east coast.

Fire destruction has been repeatedly emphasized as one of the primary
controlling factors to be considered in the interpretation of the vegetation
of the Yucatan Peninsula.1 Failure to recognize its extent and importance
is due probably to confusion of rank second growth with old hardwood
forest. The desolate area between the village of Dzitnup and Coba is a
convincing demonstration of the widespread destructiveness of tropical
forest fires.

In the reconnaissance of the forest covering the Coba ruins, a new
sculptured monument was encountered, which may be designated as Stela
25. It is located approximately 1200 feet east of Structure XXV2 in a
shrine at the edge of a low mound. The base, which leans badly, stands
to a height of 6 feet 7 inches; the upper part, broken into two large pieces
and several fragments, measures 7 feet 10 inches in length, giving the entire
stela a height of 14 feet 5 inches. Its width in the center is 4 feet 4.5 inches,
which is narrowed to 4 feet just below the rounded top. From the middle,
where it measures 13.5 inches in thickness, the monument tapers to the
edges and top to a thickness of only 8.5 inches. Only the face is sculptured.
The glyph-blocks, surrounding a large figure suggestive of those on
Macanxoc stelae, are badly eroded. An unsuccessful attempt was made to
lift the leaning base, for the sculpture on its protected face does not appear
as badly weatherworn. It is possible that a date could be obtained from
this section.

Probably less than half of the ruins of Coba have been mapped. Group
B extends to the north and northeast almost to Group D (Nohoch Mul),
and eastward past Sacbe 8. This area, through which extends the new
emergency airfield, should yield additional monuments. Two well-preserved
temples on tall substructures have been revealed by the clearing at the
east end of the airfield near Sacbe 8. Photographs of the temples, Stela 25,
and the airfield clearing have been deposited in the files of the Division of
Historical Research, Carnegie Institution of Washington.

Copan — G. Stromsvik 3

The fourth season of cooperative work by the Government of Honduras
and Carnegie Institution opened December 1, 1937. Mr. Stromsvik, in
charge, was assisted by Aubrey S. Trik and J. M. Longyear, the latter de-

1 C. L. Lundell, The vegetation of Peten. Carnegie Inst. Wash. Pub. No. 478, pp. 92-94
(1937).

2 J. Eric Thompson, Harry E. D. Pollock, and Jean Chariot, A preliminary study of the
ruins of Coba, Quintana Roo, Mexico, pi. 14. Carnegie Inst. Wash. Pub. No. 424 (1932).

3 For reports upon the investigations of 1935-1937 see Year Books Nos. 34-36.

148 CARNEGIE INSTITUTION OF WASHINGTON

voting himself to ceramic studies. Volunteer assistants were Miss Margaret
Ennis, George E. Roosevelt, Jr., Donald Barrow, and Harvey Fite.

The work of protecting the main group of the ruins against further damage
by the river is believed to have been brought to a successful conclusion dur-
ing this season; the pole dam built in 1937 withstood the summer's floods,
except for minor erosion around both ends during the peak of high water. As
had been hoped, the diversion canal dug in 1936-1937 was amply widened
and deepened by the river itself and when the floods subsided the stream
confined itself to its new course. By repairing and extending the pole dam
and by building it much higher with stone and earth removed from the ruins
it was greatly strengthened.

Mr. Stromsvik continued excavation and repair of the ball court discov-
ered in 1937. Like other Maya ball courts, it consists of a long rectangular
playing area bounded on either side by a low vertically faced bench, from
which sloping surfaces rise to a second vertical wall. The present court
differs from other known examples in having been adorned with six mono-
lithic parrot heads, three on either side (one at each end, and one at the
center of the upper edge of the sloping surfaces) . Although all six heads had
been thrown down, the butt or tenon of the center head on the east side was
found in situ, and the head at the south end of the west bench lay in such a
position that its original location could be determined. These two heads
were reset. They supply evidence which will permit eventual replacement
of the remaining four.

On the east side of the court a narrow and much weathered hieroglyphic
band runs upward from the center of the lower bench, crosses the sloping
surface, and terminates at the central parrot head. From such glyphs as
were legible Dr. Morley, in 1937, obtained a tentative reading of the date
9.17.4.0.0. In the course of this year's work it became necessary temporarily
to remove one of the slabs of the band. It proved to be a re-used stone
from a similar, earlier band, doubtless belonging to one of two older, dis-
mantled ball courts found, in 1937, underlying the present court. The stone
in question bore an excellently preserved and almost complete Initial Series
introducing glyph whose variable element represents the Venus sign, which,
according to Dr. Morley, should only occur at 9.4.0.0.0 13 Ahau 18 Yax,
approximately 260 years prior to the apparent date of the latest ball court.

General repair of the ball court comprised re-laying the flat stones of the
whole playing surface and parts of the sloping surface pavements, which had
been forced out of level by pressure of tree roots ; and rebuilding the vertical
faces of the two basal benches.

Mr. Stromsvik also replaced certain elements of the Hieroglyphic Stair-
way and of its intricately carved balustrade, and made studies looking to-
ward possible further reconstruction. To date have been added to what
remained standing of the stairway only stones whose former position was
known. Mr. Stromsvik, however, considers it advisable to complete the
entire flight. Practically all the rest of the blocks are available, and al-
though their exact original order will probably always remain uncertain,
their resetting in the stairway would not only restore to this extraordinary
construction its former impressiveness and beauty, but would preserve from

DIVISION OF HISTORICAL RESEARCH 149

damage the stones at present lying scattered in the court. Needless to say,
the elements so reset would be so marked as to distinguish them, for students,
from those found in situ and those regarding whose place there is no doubt.

Mr. Trik devoted the season to Mound 11. This work was undertaken
in order to preserve the remains of the temple and substructure, and to study
the structure as an architectural unit in the complex of the Acropolis. The
temple crowning the mound has undergone more or less excavation at vari-
ous times since Maudslay's initial work there some fifty years ago. At the
beginning of the 1938 season it was a tree-covered mound with little of the
original construction showing through the vegetation and fallen debris.

The first consideration in the clearing of the mound was protection, from
damage by material being removed from above, of the exposed sculpture of
the "Reviewing Stand" at the foot of the south slope, and of Stela N and its
altar at the base of the north side of the mound. The former was shielded
by a covering of earth and stone and Stela N was guarded by erecting a
barrier of poles halfway down the slope. Excavation was begun by opening
a passage through the central chamber to the south doorway of the temple.

Clearing the center and west part of the interior of the temple revealed
that on the north a gallery, about 30 m. long, extends the full length of the
building. There is a small central chamber, 60 cm. above the level of the
north gallery, and a small south vestibule on the same level as the north
room. In the south wall of the north room, on either side of the central-
chamber doorway, are two stair wells. The west well was completely exca-
vated and reset to a height of eight risers. Although no part of the building
exists above the spring line of the vault, it is certain that it formerly pos-
sessed a second story. This is indicated by the two stairways, by the massive
solidity of the plan, and by the fact that the walls of the north room had
been reinforced by two secondary walls about 1 m. thick, evidently built
to help support the load imposed on the vault by upper construction too
heavy for the original 3-m. span of the room.

In the floor of the central chamber an opening 1.0 m. by 60 cm. was found
at the foot of the east wall. Debris and fallen wall stones had completely
filled the opening, which proved to be the entrance to a shaft leading down
into the substructure of the building. The shaft for 2 m. down is constructed
with three step-like projections and a narrow ledge, which reduce its size to
about 75 cm. by 40 cm. At the edge of the lowest projection it is enlarged to
about 1.30 m. by 65 cm. and the walls run vertically down for 3 m. to a
plaster floor. The masonry walls are built up from the level of the sub-
structure and are an integral part of the temple construction. In the two
side walls are pairs of post holes, probably used to facilitate descent.

Many human bones and teeth, as well as animal remains, were found
mixed with the debris filling the shaft. At 25 cm. above the floor fragments
of two large stone incensario lids were found, one decorated with a hiero-
glyphic band. Enough pieces were recovered to enable Mr. Thompson to
read the date as 9.17.2.0.0 10 Ahau 8 Cumhu. Just below these fragments
was a thin layer of earth mixed with ash and charcoal containing the re-
mains of a scattered cache. Numerous obsidian blades, bird bones, human
teeth, and sherds were found, as well as parts of a deer bone beautifully

150 CARNEGIE INSTITUTION OF WASHINGTON

carved in low relief with human figures and a hieroglyphic inscription. The
remainder of the cache consisted of several small shell beads, bone tools,
and a deposit of some vegetable fiber heavily coated with red pigment.

When the shaft was entirely cleared, a circular cut was found in the floor,
the opening sealed with two rough stones. Below these were cached a small
turtle carapace, two Spondylus princeps shells, and a rough, hard green stone.

The sculptural decoration within the temple comprises two hieroglyphic
panels on the jambs of the north doorway, a highly conventionalized serpent
mask framing the doorway to the central chamber, a similar mask around
the opposite doorway of the same chamber, and two hieroglyphic jambs at
the south doorway. A new inscription was uncovered at the west doorway
of the north room. It had been concealed by the secondary construction
and was badly scattered by the falling vault and walls. All the stones were
recovered, however, and the inscription almost completely reassembled. The
date was read by Mr. Thompson as 9.17.0.0.16 3 Cib 9 Pop. Although a
great number of stones from the other panels were recovered, only a small
part could be reassembled because certain necessary pieces have not yet
come to light.

The walls and terraces of the substructure on the south side were cleared
and solidified. This operation included repair of the "Reviewing Stand,"
built out from the lowest south terrace. The stand consists of a flight of six
steps, 16.30 m. broad, leading to a battered terrace wall. The top step bears
a hieroglyphic inscription flanked on either side by a kneeling figure holding
a serpent in one hand and a scepter in the other. The steps were realigned,
the inscription repaired, and the scattered parts of the figures reassembled.
The heads and scepters of both figures had been lost until this season, when
excavation uncovered those of the west figure. The head is a magnificent
example of stone carving, well preserved and of an unusual facial type.
The parts of the east figure had been lying in the West Court, badly
weathered, but had not previously been recognized as belonging to the
"Reviewing Stand."

An unusual feature of the substructure is a series of small rectangular
niches, about 60 by 60 cm., built into the wall of the second terrace. Eight
of these were excavated and repaired. Two were found to continue into the
mound and to connect by a narrow passage. At either end of the passage is
a small chamber about 1.30 m. by 60 cm. The whole construction was
originally capped with large stones, some measuring as much as 1.70 by 0.50
by 0.35 m. No indication of the use of the chambers was found.

The west side of the mound was excavated in order to check terrace levels
and construction details. A stairway with a battered balustrade was found
to lead to the west doorway of the temple. No repair was carried out on this
side. On the north side only enough was done to recover the plan of the
temple and to reveal the condition of the fagade. Very little of the north
parts of the building remains.

Future work in the Mound 11 complex will be limited to solidifying the
foundations of the temple on the north, now in very precarious condition,
and to clearing the great stairway which descends on that side to the Court
of the Hieroglyphic Stairway.

DIVISION OF HISTORICAL RESEARCH 151

The Jaguar Stairway on the west side of the East Court was also repaired
this season with the assistance of Mr. Harvey Fite of Bard College. This
stairway, a secondary construction built over an earlier flight of steps, con-
sists of a run of eight steps built out from a terrace wall which takes the
form of a low bench about 1 m. high, a setback 60 cm. deep, and a battered
wall 1.50 m. high, topped by a wide vertical course. In the battered zone on
either side of the stairway a large rampant jaguar stands in high relief from
the wall. Very little of the wall was found in position and the jaguars had
completely fallen. Mr. Fite recovered all the parts and reassembled the
figures in the wall, repairing the broken pieces with cement. The work was
completed by resetting the terrace and realigning the stairway. A portion
of the north end of the terrace was left open in order to show the original
construction over which it was built.

Mr. Longyear this year inaugurated at Copan a series of ceramic studies
which it is hoped may be extended to cover the southeastern part of the Maya
area. The season's work was devoted to the pottery of Copan and included
the digging of a number of test pits and trenches, as well as study of sherds
and vessels recovered in past seasons while resetting stelse and running
trenches into the Acropolis. Through the courtesy of Dr. Jesus Maria
Rodriguez, Minister of Public Education of Honduras, Mr. Longyear was
able to bring a large sample of sherd material to the United States for study.

Advent of the rainy season unfortunately ended digging before excavation
of the earliest deposits was completed, but on the basis of present material,
three ceramic periods can be recognized. In the earliest or Pre-Acropolis
period, Usulutan ware, a type characteristic of the most ancient horizon so
far identified in the highlands of Guatemala and in Salvador, was introduced
into Copan. Although Usulutan constitutes a large percentage of the Pre-
Acropolis pottery, there is evidence that this ware did not make its appear-
ance until the latest phase of the period. The succeeding Acropolis period
saw the decline of Usulutan and the beginning and rise of polychrome pottery.
The zenith of Copan ceramics was reached at this time, both in variety of
types and in excellence of decoration. Carved brown ware and hematite red
ware are diagnostics for the latest phase of the Acropolis period. The last
or Post-Acropolis period was represented by material from a dump lying on
the surface of the Temple 22 pyramid. The sherds from this dump are
unlike those found in the test pits and tunnels, being largely coarse-textured,
thin-walled "utility ware/' and, from their position above the latest floors
of the temple, are believed to be the product of people who inhabited the
Acropolis after the decline of Maya civilization at Copan.

Connections between the pottery of Copan and that of other sites in the
Maya area are as yet indefinite. A few specimens of late Ulua Valley and
Lake Yajoa pottery were recovered in deposits of the Acropolis period, and
Peten polychrome types seem also to be represented here, but very meagerly.
More work must be done in the areas surrounding Copan before the latter
site can be assigned its proper place in the Maya ceramic complex.

The dating of Copan pottery periods remains vague, for tie-ins between
stratigraphical test-pit material and dated monuments and buildings have
not yet been satisfactorily determined. At present it might be suggested

152 CARNEGIE INSTITUTION OF WASHINGTON

that the Pre- Acropolis period goes back an indefinite length of time before
the early part of the ninth cycle; that the Acropolis period runs from the
early part of the ninth cycle to 9.18.0.0.0; and that the Post- Acropolis period
follows that. The Acropolis period will almost certainly be subdivided after
further digging and study.

Future work in this area should be concentrated on (a) a further study of
Copan ceramics, embracing a search for both very early and very late types
and the correlation of Copan types with dated monuments and buildings;
(b) intensive research in Salvador on the problems of pottery sequences in
that country and their relations with Copan and other areas; (c) investiga-
tions in Honduras to the east and north of Copan to determine the avenues
and areas of contact between Copan and the Ulua drainage.

Reconnaissance and Excavation in .British Honduras — J. E. Thompson

Early in 1938 Mr. Thompson made a reconnaissance of the northern part
of the Great Southern Pine Ridge of Central British Honduras in an en-
deavor to find traces of a pre-agricultural horizon. This elevated broken
area, the flora of which is pine, grass, scrub oak, and a type of palmetto, is
quite unsuited to maize cultivation, yet it was known that a number of
cairns, consisting of heaps of stones around slate shafts, were situated on
many of the highest points. Excavation of these produced negative data as
to when they were erected. No caches were found, but a few sherds includ-
ing incensario fragments and a pressure-flaked flint point among the stones
pointed to their use during the Maya period, presumably in the same way
that mountain tops were used as shrines by the Chols and highland Maya
into colonial times.

At the close of this reconnaissance a small outlying group at the ruins of
Benque Viejo (Xunantunich) was excavated. Previous work at San Jose
and Mountain Cow had revealed close similarities in the earlier ceramic
phases, but rather marked divergence in the later phases, Mountain Cow
late pottery resembling that of Uaxactun more closely than that of San
Jose. Since the connections between late San Jose and late Uaxactun (Tepeu
phase) pottery were largely indirect, and dependent on Mountain Cow, it
was thought that study of late periods at a site about halfway between San
Jose and Mountain Cow might clarify problems of contemporaneity. Benque
Viejo was chosen as being very accessible and roughly equidistant from the
three sites.

Excavation yielded three sequent phases, correctable with San Jose III,
Transition III-IV, and close of San Jose IV, and a fourth, unstratified, cor-
responding to Uaxactun la (Mamon). Since sherds from Benque Viejo of
forms occurring in Uaxactun lb (Chicanel) and Uaxactun II (Tzakol), which
in turn correspond to San Jose I and II, are in the Peabody Museum, Harvard
University, a complete series for this site now exists.

In the phase correctable with close of San Jose IV, the resemblances to
certain Tepeu features are more marked, and correspondences with Moun-
tain Cow are close in all three phases. The last Benque Viejo phase shares
with close of San Jose IV and San Jose V the absence or extreme rarity of
polychrome pottery and introduction of carved pottery.

DIVISION OF HISTORICAL RESEARCH 153

Excavation at Benque Viejo has, therefore, helped to clarify relations and
divergences between San Jose, Mountain Cow, and Uaxactun, and confirms
the disappearance of polychrome pottery toward the close of occupation
already reported for San Jose.

At the close of the season Mr. Thompson proceeded overland from Benque
Viejo to the northwest of the colony to visit a site reported by chicleros.
This, named La Milpa from a nearby chicleros' camp, lies about 7 miles
southwest of Warree camp close to the junction of the Victoria Creek with
the Bravo River.

The numerous mounds, pyramidal and razor-backed (probably collapsed
ranges of vaulted buildings), are in detached groups and are probably of
early Peten masonry style since no dressed stone was observed during the
two days spent at the ruins. Twelve stelae had stood in front of various
mounds on the east side of the main plaza. All were extremely weathered
and most had fallen face upward. Apparently three were plain; the rest
carved. Only one (Stela 7) was sufficiently preserved to yield a date. This
proved to be 9.17.10.0.0 12 Ahau 8 Pax recorded by an Initial Series on the
north side, the Calendar Round being repeated on the front. Altars stood
before some stelae. Two mounds, which seemingly formed a ball court of
the sloped-wall type and with east-west axis, are situated on the east side
of the plaza.

Mr. Thompson also visited Guatemala City to examine pottery from
Uaxactun and Kaminal-juyu, and to discuss ceramic problems with the
Chairman and Mr. R. E. Smith. He also proceeded to Copan, where he was
able to recover two more dates. A stone incensario, part of which was found
in the shaft of Temple 11, yielded (9.17.2.0.0) 5 Ahau 3 Cumhu reached from
an earlier 9.16.13.0.0, and from a jamb of Temple 11a Calendar Round date
3 Cib 7+ Pop, which is pretty surely 9.17.0.0.16 3 Cib 9 Pop, was recovered.

San Andres Tuxtla — Karl Ruppert

At the invitation of Sr. Arq. Ignacio Marquina, Chief of the Office of Pre-
historic Monuments of the Mexican Government, Mr. Ruppert as represen-
tative of Carnegie Institution spent the months of November and December
1937 in cooperative investigations with Sr. Lie. Juan Valenzuela and Sr.
Agustin Garcia Vega in the region of San Andres Tuxtla, southern Vera
Cruz.

The greater portion of the time was spent at Matacapam and on the
island of Agaltepec in Lake Catemaco. Sites near Matacanela and on the
outskirts of Catemaco were examined. Matecapam comprises over forty
mounds, of which three of the most promising were excavated in part and
trenches for stratigraphic collections of potsherds were made in two mounds
and three plazas.

One of the mounds excavated disclosed a pyramid rising in two terraces
with batter and vertical super-element. The pyramid-facing of ground
lava rock and adobe clay formed a hard durable surface which has well with-
stood the elements. A second mound, also rising in terraces, was definitely
circular. The nature of its superstructure was not ascertained.

154 CARNEGIE INSTITUTION OF WASHINGTON

All material collected was sent to the National Museum in Mexico City,
where Mr. Ruppert, on his return from the Institution's later expedition to
Quintana Roo, spent the months of June and July with Sr. Valenzuela study-
ing the ceramics. Distinctive local types for Los Tuxtlas were not deter-
mined. Pottery of the red-on-orange second period of Monte Alban and a
gray ware with incised decoration similar to that of the third period of
Monte Alban are relatively common throughout the various levels. Certain
wares are reminiscent of the Isla de los Sacrificios, and the black painted
faces of figurines common to the Huasteca also occur.

The southern Vera Cruz area is archseologically almost unknown. The
above-noted preliminary investigations have yielded valuable information
as to contacts with neighboring localities. However, the local wares must
first be identified as a foundation for future work, as they will serve to
correlate this culture with those already studied or under investigation.

Campeche Expedition — Karl Ruppert

In continuance of the exploration of southeastern Campeche and south-
western Quintana Roo, undertaken by the Institution during 1932, 1933,
and 1934, further work was done in this area in February, March, and April
of the past season. This was made possible, in part, by generous financial
aid provided by Mr. John H. Denison, Jr., who served as epigrapher on the
expedition.

Mr. Denison and Mr. William E. Shepherd, the latter as cartographer,
landed at Progreso, Yucatan, January 6, whence they proceeded to Merida.
Here they were joined by Mr. Ruppert on January 8. Mr. J. C. Brydon of
Merida kindly loaned the use of a storehouse for assembling and packing
equipment and supplies. On February 1 the expedition left Merida by train
for Hecelchekan, Campeche. The following day the journey was continued
to the chicle camp of Nohsayah (N. 18° 44.4'; W. 89° 14.6'). This portion
of the trip, made by airplane in an hour, would by pack mule have taken
ten days. February 4 the party set out with pack mules for the laguna of
Central Sabana, where camp was established from February 5 to February 8.
From here trips were made to a number of small groups of ruins lying within
a distance of from four to five hours' ride.

The first, Payan, to the east of the laguna, is a scattered group of mounds.
The highest, which was probably the principal structure of the group, now
shows only a few great stone blocks which served as facing. At some distance
to the southwest are remains of a building which shows fourteen chambers.
The west facade is pierced by three doorways and was decorated with stucco
masks.

Desprecio, two hours' ride southeast from camp, is distinctive only in a
U-shaped structure somewhat reminiscent of similarly shaped mounds seen
at Rio Bee in 1933.

Buenos Aires, lying four hours' ride northeast of camp, was a group of
low mounds and a partially standing six-chambered building. The structure
carries a roof-comb of the single-wall type. Xaxbil, near the aguada of
Garafon, is a small building with two rooms, and has fagade decoration of
large geometric scrolls and engaged columns at the corners.

DIVISION OF HISTORICAL RESEARCH 155

On February 11 the expedition moved to Lagunita (N. 18° 27.6'; W. 89°
18.9') , where camp was maintained until February 18. The site of Okolhuitz,
to the east of the aguada, is fairly large and arranged in two definite groups,
each on the crest of a low ridge. Architecturally it is of Rio Bee type.

A day's trip was made to the site of Pasion del Cristo, where there are a
great many large mounds and three fallen and one standing stelae. No dates
were obtained by Mr. Denison.

Three days were necessary to make the trip from Lagunita and examine
the site of Corriental. In this group is one standing building with two towers.
A passageway from a chamber behind one tower extends downward into the
fill of the pyramid, through it to the other side, and then upward opening
into a chamber behind the second tower.

From February 19 to February 25 the expedition camped at the aguada
of Xpuhil (N. 18° 30.6'; W. 89° 24.5'). The ruins, lying twenty minutes'
walk southwest of the aguada, consist of a few low mounds, except for one
remarkable structure defining the west side of a large plaza. This building
has twelve rooms and three towers, one placed at either end and one in the
back center. The latter rises 20 m. above the podium on which the building
rests. The towers have rounded corners and carry false stairways which
were ornamented with great stucco masks.

On February 26 camp was moved to Aguada Carolina, and the following
three days were spent in studying the ruins of Culucbalom, half an hour's
ride to the east. The best-preserved structure defines the north side of a
small court. The building contains six chambers and carries a roof-comb
of the single-wall type. Of special interest is the south facade, ornamented
with four engaged columns each decorated with two seated human figures in
low-relief stucco.

While camped at Laguna Carolina Mr. Shepherd made observations for
latitude and longitude, which are N. 18° 34.1' and W. 89° 27.7', respectively.
The aguada at water level had a length of % mile and a width of % mile.
On March 3, Mr. Denison made a trip to inspect some large mounds to the
south. They proved to be Becan, the site surrounded by a moat, which was
discovered by Carnegie Institution in 1934.

On March 7 the expedition left Aguada Carolina for Santa Rosario by way
of So Aguada, Guitara, Carmalita, and Holaltun. A large group of mounds
at Carmalita indicates a once well-planned, carefully laid out city. To the
northwest of Holaltun recent milpa clearings have exposed a number of struc-
tures. The lure of treasure has led chicleros to dig in some of the chambers
with consequent destruction of material.

The aguada of Santa Rosario was reached March 14 and there camp was
maintained until the morning of March 22. The ruins known as Pechal lie
half an hour's walk to the south of the aguada (N. 18° 52.0'; W. 89° 29.80 •
The city was the largest encountered. Several of the buildings, each resting
on a podium, show elaborate stucco-decorated fagades. The east court
proved of outstanding interest, as it was probably an amphitheater. The
court measures 68 m. by 75 m. and is surrounded on all sides by a continuous
mound broken only in four places, as if for entrances. An examination of
the enclosing wall showed it to be lined on the inner side by a series of

156 CARNEGIE INSTITUTION OF WASHINGTON

eighteen to twenty steps. The seating capacity, very conservatively esti-
mated, is placed at 8000. Four stelse discovered at Pechal were sculptured
with human figures, but carried no dates.

The last site visited was that of Peor es Nada (N. 18° 50.5'; W. 89° 22.2'),
where the party stayed from March 22 to March 31. It is a rather extensive
site with a number of buildings standing in part, which show ground plans
of from six to fourteen rooms. Towers, as at Rio Bee, were seen on two
structures, and there is a roof-comb of the single-wall type, 18 m. long, 5.35 m.
high, and 1.90 m. wide. Peor es Nada is the only site where a ball court was
found. From here the expedition returned to Noh-Sayab and then by air-
plane, on April 6, to Merida.

Study of Maya Sculpture — F. B. Richardson

In attack upon the problems of any archaeological area certain definite
processes are indicated. First must come a preliminary stocktaking of
remains, their general nature and their distribution. The second step should
be the chronological ranking of those remains, in order to determine the
extent and the location of population at different periods, and also to make
clear the trends of cultural change. For this chronological ranking one
should select types of evidence which most clearly reflect the passage of
time.

In the Maya field the Initial Series dates supply the most obvious ma-
terial for the establishment of sequences; and during the early years of
Maya research they were relied upon almost exclusively. But while these
inscriptions are of the greatest value as chronological landmarks, they cover
a period of only about five hundred years. They supply, therefore, no evi-
dence regarding the obviously long developmental stage which preceded the
erection of the earliest monuments ; and Initial Series ceased to be recorded
several centuries before the coming of the Spaniards. Furthermore, monu-
ments are few or lacking at many sites even of the epoch of greatest inscrip-
tional activity; and none at all occur in the important peripheral districts.

For this reason it is necessary, in an attempt to deal with the whole area
and the entire span of Maya history, to include intensive study of criteria
other than epigraphic. Of these, pottery and the details of architecture are
among the most useful and have been made the subject of special researches
and surveys by the Division. Of almost, if not quite, equal importance is
sculpture, an art in which the Maya were preeminent among the prehistoric
peoples of America.

Maya buildings were lavishly decorated with carvings in stone and with
figures modeled in stucco. The monuments bearing the above-mentioned
hieroglyphic dates were also elaborately sculptured and, as Spinden demon-
strated some years ago, it is possible by means of the dates on the stelse to
establish the trends of sculptural technique. Conversely, the nature of
their carving permits determination, in many cases, of the age of stelae whose
inscriptions have become undecipherable through breakage or the erosion of
time. The stylistic evidence offered by sculpture has therefore come to play
a significant role in epigraphic as well as in architectural research. Further-
more, there are important linkages between sculpture, jade carving, and the

DIVISION OF HISTORICAL RESEARCH 157

decoration of pottery. Finally, Maya art formed an integral part of the
larger art field of Middle America. It influenced, and was influenced by,
the work of other neighboring cultures.

The study of sculpture is thus of great importance; but the mass of sculp-
tural and closely allied material is so great, and artistic and technical prob-
lems are so many, that epigraphers, ceramicists, and students of architecture
must rely upon others for the highly specialized sculptural data they require.
For this reason Mr. F. B. Richardson has undertaken a detailed survey of
this aspect of Middle American culture.

The ultimate objective of Mr. Richardson's study is the comparison of
Maya sculpture with similar developments in other parts of the world. In-
cluded among the immediate problems are: interrelation with adjoining cul-
tures ; identification of sculptural foci ; tracing of trait diffusions within and
without the Maya area; determination of the origin, the chronological devel-
opment, and the influence upon the other arts of Maya sculpture. Such an
investigation should contribute toward clarifying the history and society
of the Maya.

The activities of Mr. Richardson, previous to the field season of 1938, were
confined to the gathering of a comprehensive photographic file, and to ex-
amination of museum collections and the literature of the subject. During
the winter of 1938, he made a rapid reconnaissance to the south and west of
the Maya area, gathering data on regions which are archaeologically little
known. The season's work was devoted to four districts: western Salvador,
the Pacific area of Nicaragua, southwestern Honduras, and the central
Pacific coast of Guatemala and the adjacent highlands.

In western Salvador, Mr. Richardson examined El Limon, El Congo, Las
Siete Princesas, Casa Blanca, Quinta Elena, and Tazumal, all in the depart-
ment of Santa Ana. In addition, he visited collections in Chalchuapa and
Santa Ana, notably those of Sr. Carlos Alvarez L. and Sr. Luis Fredrico
Mathies. En route from Guatemala City to Santa Ana and thence to San
Salvador, he stopped at Asuncion Mita, noticed mounds near Plata and Los
Esclavos in Guatemala, and at San Andres in Salvador. In San Salvador
he examined collections of the National Museum, of Dr. Oscar E. Salazar,
Dr. Alfonso Quinones, and Mr. Schmidt.

In Nicaragua, Mr. Richardson visited Asososca, Nejapa, Nindiri, Diri-
amba, Masaya, Masatepe, and Granada. The major part of the work, how-
ever, consisted of studying specimens in the collections of the National
Museum, the Presidential Palace, Sr. David Sequeira, Dr. Joaquin Gomez,
Dona Josefa Vde. de Aquierre, Mr. F. Bunge, Mr. R. E. Frizell, Mr. R. E.
Harding, Mr. F. Dreyfus, Mr. Maurice Marragou, Mr. Alfred Bequillard, Mr.
Morelock, Sr. Jose Maria Gutierrez, Sr. Constantino Marenco, Mr. Arthur
Vaughan, and the Jesuit College.

En route from Nicaragua to Gracias, southwestern Honduras, Mr. Richard-
son stopped in Tegucigalpa to study and photograph material in the Honduras
National Museum. From Gracias he rode down the valley of the Rio Mejo-
cote visiting the sites of Las Flores, Tapusuna, and Sehuatepeque. He then
continued on to the valley of the Rio Alash, reporting ruins at Cucuyagua
and La Union, the latter being fairly extensive and having been called to

158 CARNEGIE INSTITUTION OF WASHINGTON

his attention by M. Rafael Girard through Dr. Jesus Maria Rodriguez, Minis-
ter of Public Education of Honduras. In this same valley near the towns
of El Corpus, Corquin, Sensenti, and San Marcos, sites were reported to, but
not investigated by him. With Santa Rosa as a base, two unsuccessful days
were spent trying to locate ruins reported by E. G. Squier in 1854, lying
roughly about sixteen kilometers to the north of Santa Rosa. A subsequent
three weeks' stay at Copan enabled Mr. Richardson to benefit from the ac-
cumulated results of many years' work at that sculpturally richest of all
ancient Maya cities. He also spent five days at Quirigua, whose stelae are
of outstanding artistic importance.

On the Pacific coast of Guatemala Mr. Richardson reconnoitered the low-
land sites of Monte Alto and La Flora, El Baul on the slope of the divide,
and the highland sites of El Duranzo, El Naranjo, and Villanueva. From
the lowland towns of Obero and Masagua, and the highland towns of Tecpan,
Itzapa, El Tejar, and Antigua, sculptures not in situ were recorded. While
in Guatemala City he studied collections at the National Museum.

The season's work necessitated frequent airplane travel allowing cursory
geographical observation. In addition, reports gathered indicated unrecorded
remains in areas surrounding those visited.

Such an extended itinerary opens up new vistas for future research and
contributes toward a more adequate understanding of existing problems. The
Pacific coast of Central America has long been recognized as a route of migra-
tion. Within this area in Guatemala, Salvador, Honduras, and Nicaragua,
there appears to be a distinction between lowland and highland cultures.
Certain traits are localized, while others cover a relatively large area. The
"Chorotegan" sculpture of Nicaragua was found to have no close relation-
ship to that of other known areas. Evidence gathered tends to weaken the
hypothesis that the Chorotegan culture antedated that of the Maya. Cer-
tain sculptures from southern Vera Cruz, Tabasco, and northern Chiapas
are believed to have affiliations with those of the Pacific coast of Guatemala.
The Rio Lempa in eastern Salvador apparently is close to the fusion point
of northern and southern traits. In the department of Chontals, Nicaragua,
remains differ from those of the lake region.

In Honduras, the archaeologically fertile and hitherto unexplored Alash
River valley produced, among other sites, one with definite Maya traits in
conjunction with surface material of non-Maya character.

Geographically and in part culturally the Guatemala highlands have much
in common with western Salvador. The headwaters of the Rio Alash inter-
lock with those of the Rio Lempa and together with the Rio Mejocote they
join to form the Rio Jicatuyo. With the exception of the Comayagua Valley
drainage, the Rio Jicatuyo is the largest tributary of the Ulua River. It
would therefore seem that further investigations in the western half of Sal-
vador and in the Alash Valley should contribute toward a more adequate
understanding of the Guatemala highlands and of the similarity between
ceramic material from Salvador and that of northwestern Honduras. Under
the Institution's present program Nicaragua lies too far afield for immediate
additional attention. Further work on the Pacific coast of Guatemala should
help to determine the geographical limits, chronological sequence, and routes

DIVISION OF HISTORICAL RESEARCH 159

of migration of certain Middle American cultures. That area, accordingly,
would seem most important for intensive study.

Minor Archaeological Studies in Guatemala — R. E. Smith

Small clay figurines, for the most part in the form of human effigies, are
among the most characteristic and, archaeologically, the most significant re-
mains of the so-called "Archaic" culture of Middle America. They were also
produced in large quantities by the Maya, the Toltec, the Aztec, and other
people of later times.

Mr. Smith, in his work upon the pottery of Uaxactun, has been giving spe-
cial attention to the figurines from that site. The earliest figurines of Uaxac-
tun have proved to be similar to specimens from apparently very old cultures
in the Guatemala highlands; and these, in turn, seem allied to the Archaic
figurines of Mexico. Mr. Smith has accordingly been led to the making of a
comparative study of all such material, that from Mexico as illustrated in
the many publications of Vaillant; that from the Guatemala highlands com-
prising the collection made by Dr. Ricketson and the Chairman in 1935 at
Finca Miraflores, and by the Chairman in 1936 and 1937 at La Esperanza,
both localities which form part of the great archaeological site of Kaminal-
juyu.

The Kaminal-juyu figurines were found by Mr. Smith to include several
distinct types. But the specimens from La Esperanza having come from
disturbed deposits, and those from Miraflores from a very small excavation,
provided no information as to whether the observed types were contempo-
raneous variants or whether they represented a stylistic sequence.

In order to gather further data Mr. Smith excavated a new and larger sec-
tion at the Finca Miraflores, isolating a square column of earth, recording its
layers, and collecting all material in stratigraphic order. Great numbers of
potsherds were recovered, which add significantly to our knowledge of the
early ceramics of the region. The figurines, of which over fifty came to light,
are at present being studied by Mr. Smith.

Mr. Smith also made a trip, during the spring, to Tiquisate on the Pacific
coast plain of Guatemala, where the extensive operations of the United Fruit
Company have led to discovery of many archaeological remains. These have
been noted, and arrangements have been made with the Company officers at
Tiquisate for notification of the Institution's office in Guatemala City of
further finds.

Ceramic Technology — Anna 0. Shepard

The plan of the Ceramic Technology Project has been to conduct con-
currently studies of both Maya and Anasazi (Basket Maker-Pueblo) pot-
tery. This division of effort is advisable because the archaeological investi-
gations of the Division are being conducted both in the Maya field and in
southwestern United States, and also because a greater diversity of materials
and problems is thus presented. The methods of pottery making in the
two areas are in many ways distinct and the course of ceramic development
differed. A broader knowledge of primitive techniques is therefore gained,
and, at the same time, opportunity is afforded to work out the evidence of

160 CARNEGIE INSTITUTION OF WASHINGTON

culture contacts and influences as shown by trade in pottery and spread of
specialized techniques of pottery making at two levels of cultural develop-
ment. The purpose of the technological laboratory is to make extensive
and systematic investigations which may be expected to yield data of gen-
eral historical interest, rather than to provide facilities for analyses to be
used for miscellaneous and unrelated identifications. Cooperative studies
with other institutions are therefore made only when material contributes
to the solution of the broad problems outlined for investigation.

Research in the Maya field during the year centered mainly around the
completion of technological notes on the pottery of San Jose, British Hon-
duras, for Mr. Thompson's report on this site. The various pastes had in
the main been identified the previous year, but more detailed studies and
comparisons with pottery from Uaxactun showed definite possibilities of
tracing to their source a portion of the limestone-tempered pastes which are
so widely distributed in the lowland region. The tuff-tempered wares re-
garded as intrusive in San Jose were reexamined for comparison of properties
of the tuff with that in pottery from Copan, San Agustin Acasaguastlan,
Kaminal-juyu, and Zacualpa. The study of San Jose pastes was supple-
mented by the microscopic examination of sherds from Holmul, Tayasal,
and Baking Pot in the Peabody Museum at Harvard. As the paste of over
1400 sherds was identified, our knowledge of the distribution of tuff-tem-
pered wares in the lowland region, a phenomenon of primary interest because
of the questions of trade which it raises, was extended; and the necessity of
considering frequency of occurrence in relation to natural resources was
demonstrated. The marked differences in the proportion of tuff temper,
both by period and by ware, in the various sites shows that distribution and
relations are complex. Extensive studies will accordingly be necessary in
order to determine the full significance of the numerous occurrences of tuff-
tempered pottery in the limestone area.

Maya potters gave especial attention to vessel finish ; and brightly colored,
highly lustrous surfaces are characteristic of the monochrome slipped wares
of the Peten. The properties of these slips indicate the use of specialized
techniques which should provide important clues for study of the spread of
traits. A number of different experiments were made to determine whether
or not these surfaces were coated with some organic material after firing and
the effect of such material, if present, on luster and color. Some positive
evidence was obtained and a number of problems outlined for future
investigation.

Work in the Anasazi area centered around the study of material from
Mr. Morris' excavations in the Four Corners region and the initiation of a
more extensive study of Rio Grande glaze-decorated ware. The petro-
graphic examination of La Plata pottery had shown a few intrusive sherds
containing a distinctive igneous rock — a poikilitic sanidine basalt. This
rock was identified with that which occurs abundantly in corrugated pottery
from Chaco Canyon. In order to gain some notion of frequency of occur-
rence in Chaco pottery, over 2000 sherds from stratigraphic tests made by
the Pueblo Bonito expedition were examined through the courtesy of Mr.
Neil M. Judd. Although its proportion is high, no source of this rock is

DIVISION OF HISTORICAL RESEARCH 161

known in the Chaco, and in October a field trip was made to examine igneous
rocks in the Navajo country east of the Chuska Mountains and to collect
sherds from ruins in that district. The occurrence of the above-mentioned
basalt in the Chuska Mountains and its consistent use for temper in sites
of the Chuska region raised the question whether or not the ancient
Chuskans were specialists in the manufacture of corrugated ware, from
whom pueblos to the east and north obtained a portion of their corrugated
vessels. On the same field trip, the Red Rock country was visited in connec-
tion with studies of Mr. Morris' Basket Maker III pottery from this area.
Here problems center around the absence of coarse quartz sand and buff-
burning clay which characterize the bulk of the early Red Rock ware. Ex-
amination of entire vessels in the Red Rock collection and a study of sherds
shows the presence of igneous rock temper, some of which is certainly
intrusive.

Rio Grande glaze-decorated pottery offers an exceptional opportunity to
investigate the development and spread of a specialized technique, since the
area is well defined. Geologic formations within it are diverse with conse-
quent wide variations in pottery materials, and changes in style are suffi-
ciently definite to form time markers. The possibility of recognizing
through which villages glaze ware was introduced and how rapidly its manu-
facture spread was brought out in the Pecos investigation and was again
demonstrated this year when a report was made on pottery from Unshagi in
the Jemez Canyon for Mr. Paul Reiter of the State Museum of New Mexico.
It was therefore decided to make a general survey of Rio Grande glaze ware,
the work being initiated and outlined by the examination of sherd col-
lections in the Laboratory of Anthropology at Santa Fe, made available by
courtesy of Mr. Kenneth M. Chapman.

The principal advance made in the Ceramic Technology Project during
the year was in extending the scope of the work to include chemical analysis.
Simple qualitative tests and a few quantitative determinations had pre-
viously been carried out, but adequate facilities for chemical analysis were
not available until the project was moved to Boulder in October. A labora-
tory was then equipped and the essential apparatus for micro-qualitative
and micro-quantitative analyses obtained. Basic training in analytical
chemistry and micro technique was taken by Miss Shepard during the year
while devoting full time to her regular duties.

Maize Investigation — R. Stadelman

In previous reports there has been made clear the outstanding economic
importance of maize throughout Maya history. There has also been stressed
the significance, for studies of the rise and diffusion of native New World
culture, of determining the place of this cereal's origin. The latter problem
has been under attack for several years by Mr. J. H. Kempton of the United
States Bureau of Plant Industry in cooperation with Carnegie Institution.
During the past year Mr. Kempton, using material gathered on former field
expeditions, has been engaged in laboratory investigations of the genetics of
teosinte, a plant suspected to have been involved in the ancestry of maize.

162 CARNEGIE INSTITUTION OF WASHINGTON

Mr. Kempton has also directed the study which Mr. Raymond Stadelman
has been making of maize agronomy in the highlands of Guatemala.

Mr. Stadelman took up residence in January 1937 at the Indian village of
Todos Santos in the department of Huehuetenango, Guatemala, as reported
in the last Year Book. He has now observed and recorded in detail the agri-
cultural practices of a typical Indian community throughout a full agricul-
tural year. This has enabled him to prepare a list of definite questions
regarding the agronomic and economic aspects of maize culture which he is
at present using for an extended survey of other towns in the highlands. The
intensive and extensive information being obtained by Mr. Stadelman will
provide, for the first time, accurate data upon farming in the mountainous
parts of Guatemala, which will be of great value for comparison with similar
data already collected by Messrs. Kempton, Emerson, and Steggerda in the
lowlands of northern Yucatan.

Ethnological, Sociological, and Linguistic Research — R. Redfield,
M. J. Andrade, S. Tax, A. T. Hansen, A. Villa R.

As indicated in the preceding Year Book (p. 145) , Mr. Villa's expedition
to Quintana Roo in the winter of 1936-1937 completed the field work for
the study of village and city life in the peninsula of Yucatan. Mr. Villa spent
part of the year 1937-1938 in preparation of his report on the east central
Quintana Roo villages ; it is expected that this will be ready for publication
by January 1, 1939. Dr. Hansen devoted part time to further work on his
monograph on Merida; this should be ready in 1939. In the summer of 1937
Dr. Redfield began the preparation of the summary and comparative volume
on culture and civilization in Yucatan.

The comparative study of highland societies of Maya peoples was pros-
ecuted during the year here reported by Dr. Tax and by Mr. Villa. Dr.
Tax's year was chiefly devoted to preparing for publication material collected
during the two previous seasons in Panajachel, Guatemala. After returning
from the field in June 1937, field notes and data contained in such forms as
genealogies, schedules, and maps were organized. At the same time a draft
of one chapter of the report was written to see if the purely "cultural" data —
the knowledge, beliefs, technology, science, values, and modes of behavior —
could not be best presented from the native point of view almost as if an
Indian himself were writing it. Since the method appeared fruitful, it is
being continued.

During the last six months of 1937 Sr. Juan Rosales, an Indian of Pana-
jachel trained in field methods by Dr. Tax and Dr. Andrade, remained in
Panajachel to collect additional data and to resolve questions put by Dr.
Tax. This necessitated considerable correspondence. At the same time,
Mrs. Tax devoted herself to notes transmitted by Rosales.

At the end of December, Dr. Tax left again for Guatemala, taking up resi-
dence in Panajachel. During the three months that followed, he accom-
plished three missions: first, he filled in and completed his studies of Pana-
jachel culture, clearing up doubtful points for his report; second, he installed
Sr. Rosales in the town of San Pedro la Laguna, there to do an ethnological
study under his direction, and conferred with him a half-dozen times both

DIVISION OF HISTORICAL RESEARCH 163

in San Pedro and in Panajachel; and third, he made practical arrangements
for his and for Dr. Redfield's next field seasons. In the course of this work,
much was learned about house building and about the relations of Indian and
ladino laborers and artisans in Agua Escondida; and as a house in Chichi-
castenango was taken only after many vain attempts to obtain land or a
house owned by Indians, considerable new insight into Chichicastenango
attitudes and modes of living was attained.

At the beginning of April Dr. Tax returned to resume work on his Pana-
jachel report, now devoting himself to writing. By the end of June some-
thing more than two hundred pages of typescript were ready and almost as
many more in various stages of preparation. Plans call for the virtual com-
pletion of the report by the beginning of October, when Dr. and Mrs. Tax
will resume work in Guatemala, returning to Chichicastenango to complete
the study begun there in 1934-1935.

By this time the sociological and ethnological problems to which attention
is being directed are more clearly delineated, and the work should go on more
rapidly. By the end of another year intensive studies of three communities
(Panajachel, Chichicastenango, and San Pedro la Laguna), representing the
three linguistic divisions of the midwestern highlands, will probably have
been completed ; it will then be possible to undertake comparisons of a more
intimate nature than those afforded by the reconnaissance and surveys of
the past.

The work done in connection with this project, as well as that done by
others, notably La Farge and Schultze-Jena, has indicated many common
resemblances as well as certain important differences among the Maya of
the highlands of Guatemala, and the facts available have further suggested
that the peoples of eastern Chiapas form a part of the same general type and
region. Accordingly it is desirable to extend the guided sampling of Maya
ethnology to Chiapas. Notes on the Tzeltal, Tzotzil, and Choi have been
provided by Pineda, Starr, Blom and La Farge, Becerra, and others ; but the
information provided in their notes is inadequate to enable us to determine
the significant problems in this area. Accordingly Mr. Villa spent two months
early in 1938 making a reconnaissance of Tzeltal settlements. San Cristobal
de Las Casas served naturally as a base. Fifteen communities, from Ama-
tenango on the south to Petalcingo on the north, were visited; these included
both highland and lowland settlements. From a few hours to several days
were spent in each community. Mr. Villa strove to secure his ethnographical
information from the Indians, rather than from the ladinos, and to investi-
gate matters such as type of settlement, Indi&n-ladino relationships, and form
of government, as are summarized for the communities of the midwestern
highlands of Guatemala in a recent paper by Dr. Tax (American Anthropol-
ogist, vol. 39, pp. 423-444, 1937).

It is expected that the material secured by Mr. Villa will be published
in a short article, but some of the suggestive findings may be mentioned here.
Brief mention of Indian surnames among the Tzeltal is made by Starr;
nothing is said on the subject by Blom and La Farge. Villa has established
the fact that the highland Tzeltal have exogamous surname groups; the names
are descriptive, or refer to animals or plants. Furthermore, certain of the

164 CARNEGIE INSTITUTION OF WASHINGTON

highland villages are divided into antagonistic sub communities (calpules),
one with lands to the north, the other with lands to the south. In Oxchuc
a principal annual ceremony attends the transfer from one calpul to another
of a certain sacred book. This book, a manuscript containing apparently
orders set down by Spanish authorities in the seventeenth century, is kept
in a special sacred structure. Villa obtained further information on the
nineteen-month calendar; it is apparent that it is still used in connection
with the agricultural round.

It is expected that this reconnaissance will be followed by a more inten-
sive study, to be carried on by Mr. Villa, of one of these Tzeltal communities.

Dr. Andrade continued the preparation of his linguistic manuscript of
Yucatec; it is expected that it will be ready for publication in the spring
of 1939.

Publications, Section of Aboriginal American History —
Margaret W. Harrison

In June 1938 a collection of twenty-four taxonomic papers was published
under the title Fauna of the caves of Yucatan. In these papers A. S. Pearse
of Duke University and his collaborators include data on many hitherto
unreported species. This publication forms a companion volume to The
cenotes of Yucatan, a zoological and hydrographic survey, which appeared
in 1936.

A medical survey of the Republic of Guatemala by George Cheever Shat-
tuck of the Harvard School of Public Health, and four collaborators, will
be published in August 1938. The material is based upon medical observa-
tions made in Guatemala by Dr. Shattuck and Dr. Curth, and upon informa-
tion on the distribution and prevalence of diseases in the republic, as shown
by data collected from various public and private sources. Medical prob-
lems of special interest are discussed in detail, and outstanding public-
health questions are considered briefly. The text is fully substantiated by
statistical tables.

In Modern Maya houses: a study of their archaeological significance, Rob-
ert Wauchope describes modern Maya architecture in detail, both as an eth-
nographic record and to facilitate interpretation of prehistoric house re-
mains. He devotes particular attention to abandoned houses and to the re-
maining traces of their superstructures. Verbal, documentary, linguistic,
functional, and archaeological evidences of the age and geographical distri-
bution of constructional features are considered, and several ethnological
problems are proposed. The volume, extensively illustrated, will be pub-
lished in August 1938.

Progress has been steadily made on the proof of The inscriptions of Peten
by Sylvanus G. Morley. One volume of plates was published in 1937 and
it is expected that the four volumes of text will appear before the end of
1938.

The Titles of Ebtun by Ralph L. Roys is now in press. This book is a
study of the archives of Ebtun, an Indian town in eastern Yucatan (1600-
1833). The documents, in Maya and Spanish, comprise agreements with

DIVISION OF HISTORICAL RESEARCH 165

other towns, transfers of property, and records of lawsuits, furnishing a
historical link between the sixteenth-century inhabitants of this region and
the present population. Following a historical introduction, the documents
are transcribed, translated, and annotated.

The manuscript of Excavations at San Jose, British Honduras by J. Eric
Thompson is also in press. Whereas most excavations in the Maya area
have been confined to the impressive ceremonial centers, the culture here
described is that of a small town, which may be considered more typical of
the general culture level. The architecture, pottery, artifacts, and caches of
San Jose are discussed. The section on ceramics, fully illustrated, is ampli-
fied by the inclusion of Anna 0. Shepard's study on the pastes and slips
of San Jose pottery.

The manuscript of a small paper entitled The age and provenance of the
Leyden Plate has been completed by Frances R. and Sylvanus G. Morley.
This paper will form one of the Contributions to American Archceology and
will probably go to press before the end of 1938.

Earl H. Morris has finished the manuscript of a large report, Contribu-
tions to the archceology of the La Plata district: southwestern Colorado and
northwestern New Mexico. An appendix on the technology of La Plata
pottery has been written by Anna 0. Shepard.

SECTION OF POST-COLUMBIAN AMERICAN HISTORY

History of the United States

The fourth volume of Leo F. Stock's Proceedings and debates of the
British Parliaments respecting North America was published in November
1937. Dr. Stock will spend the summer of 1938 in England, gathering ma-
terials for the final volumes in this series. In August he will represent the
Institution at the Eighth International Congress of Historical Sciences at
Zurich.

The third and final volume of Historical documents relating to New
Mexico, Nueva Vizcaya, and approaches thereto, to 1773 was published in
January 1938. These documents were collected by Adolph F. A. and Fanny
R. Bandelier, and edited by Charles W. Hackett of the University of
Texas. The first two volumes include the Spanish texts accompanied by
English translations; the third volume contains translations only.

Under a post-retirement grant, Edmund C. Burnett has been engaged
in preparing a volume interpretative of the Continental Congress, 1774—
1789, and based primarily on the eight volumes of his Letters of members
of the Continental Congress. A large part of the book is written and
most of it has been revised.

The annual List of doctoral dissertations in history now in progress at
American universities was compiled by Margaret W. Harrison, editor of the
Division. The issue of December 1937 contained 1040 titles of theses upon
which candidates for the doctorate in history were engaged. This pamphlet
is published by the Division of Historical Research and is distributed to

166 CARNEGIE INSTITUTION OF WASHINGTON

libraries, educational institutions, members of university faculties, and
periodicals in the field of history.

David M. Matteson, indexer of publications emanating from the Section
of Post-Columbian American History, prepared the indexes to the above-
mentioned volumes by Dr. Stock and Dr. Hackett.

During 1937 and 1938 work on the Guide to the materials for American
history in the libraries and archives of Paris was continued by John J. Meng
under the supervision of Waldo G. Leland. The manuscript notes prepared
by Dr. Leland and M. Abel Doysie in years past are being analyzed, coordi-
nated, and in some cases amplified, in preparation for definitive publication.
Thus far, attention has been confined to the French Foreign Office archives,
which are extensive enough to require a separate volume of the Guide de-
voted solely to their analysis. Approximately three-quarters of the material
for this depository has been gone over and analyzed in a first draft that will
need little, if any, revision before submission to the printer. The material
covered thus far includes all the "correspondance politique" with the excep-
tion of a few volumes in the "fonds Espagne," which latter volumes will be
disposed of within the next two months. There remains the much smaller
group of materials for the "memoires et documents" section of the archives.
It is hoped that all remaining work on the Foreign Office archives will be
completed before the end of the present calendar year. It should therefore
be possible to publish an additional volume of the Guide, devoted to the
Foreign Office, during the course of 1939.

It should be noted in addition that a few important lacunae in the notes
already at hand are being disposed of by M. Doysie, working in Paris under
a special grant. With these lacunae taken care of, the resulting analysis
of the Foreign Office archives should be reasonably complete from the
earliest years to 1840, in some cases even as late as 1870.

History of Yucatan

During the past year Sr. J. Ignacio Rubio Mane has continued his search
for materials on the colonial history of Yucatan in the Archivo General de
la Nacion in Mexico City. The volume-by-volume survey of the Ramo de
civil, which had progressed as far as volume 1250 by July 1, 1937, was carried
through to volume 2302, the last in the series. The uncatalogued part of the
Ramo de tierras, volumes 2972 to 3623, has also been searched. In these
two ramos a mass of new material for the history of Yucatan, especially for
the eighteenth century, has been found. The documents deal with govern-
mental organization and administrative policy, ecclesiastical affairs, Indian
administration, encomiendas, the economic history of the province, suits over
lands, and private business transactions. A series of expedientes relating to
the abolition of the encomienda system in 1785-1786 deserves special notice.
Photographic reproductions of several important items have already been
made and others will be reproduced during the year 1938-1939. After com-
pleting his work on the above-mentioned series, Sr. Rubio Mane started a
survey of a number of less extensive series, such as Arzobispos y obispos,

DIVISION OF HISTORICAL RESEARCH 167

Real audiencia, Expolios, Real acuerdo, etc. He will be engaged in this work
during the greater part of the coming year.

Dr. Robert S. Chamberlain spent two months (July 17 — September 24,
1937) in Mexico City, after completing his investigations in the archives of
Guatemala, El Salvador, and Honduras. During this time he examined sev-
eral sections of the Archivo General de la Nacion, especially the papers of the
Hospital de Jesus, as well as parts of the Archivo de Notarios, the Archivo
del Ayuntamiento, and the Cathedral archive. Unfortunately, very few
documents pertinent to his investigations on the history of the conquest of
the Maya area were found.

Since his return to the United States in October 1937, Dr. Chamberlain has
been engaged in the preparation of certain materials for publication. A
resume of the history of the conquest of Yucatan, based on the more extensive
and detailed sections of his projected history of the conquest of the Maya
area, has been largely completed. This will be incorporated in the intro-
ductory section of the work on the life and times of Fray Diego de Landa
being prepared by Mr. Scholes. Dr. Chamberlain has also written a prelimi-
nary draft of a chapter on the exploration and conquest of the Acolan-Tixchel
area which will form part of the larger work on the cacicazgo of Acolan-
Tixchel on which Mr. Roys and Mr. Scholes are also collaborating. During
the last three months of the year 1937-1938, Dr. Chamberlain devoted most
of his time to the preparation of a short monograph on the Castilian origin
of the encomienda system, which should be ready for publication by the
autumn of 1938.

Mr. France V. Scholes and Miss Eleanor B. Adams gave most of their time
during the past year to the preparation of two volumes on the administra-
tion of Don Diego Quijada, who served as alcalde mayor of Yucatan from
1561 to 1565. It was hoped that the manuscript of this work would be fin-
ished before the end of 1937, but the decision to add a considerable number
of documents to the series as originally planned made it necessary to carry
the work over into 1938. These volumes, which are now in press, will con-
tain eighty-five documents and a lengthy introduction. The latter will de-
scribe the development of Yucatan from 1550 to 1561, the beginnings of the
Quijada regime, the famous investigation of Indian idolatry made by
Quijada and Fray Diego de Landa in 1562, the increasing resentment in-
spired by Quijada's government, especially his attempt to abolish burden
bearing, the residencia of the alcalde mayor, and the final vindication of
Landa for his share in the unhappy events of 1562. As stated in the Year
Rook for 1937, the material published in these volumes will provide the
documentary basis of part of the work on the life and times of Landa being
prepared by Mr. Scholes with the collaboration of Dr. Chamberlain, Miss
Adams, and Sr. Rubio Mane.

Mr. Scholes spent part of November and December 1937 in Mexico City in
conference with Sr. Rubio Mane and in negotiations with the editor and pub-
lisher of the Biblioteca historica mexicana series, in which the two volumes
on Quijada are to appear. Late in June 1938, Miss Adams left for Mexico
City, where she will spend several months carrying on investigations in the
Archivo General de la Nacion in collaboration with Sr. Rubio Mane.

168 CARNEGIE INSTITUTION OF WASHINGTON

During the past year volumes II and III of the Documentos para la historia
de Yucatan, edited by Mr. Scholes, Sr. Carlos R. Menendez, Sr. Rubio Mane,
and Miss Adams were published. Volume II contains a series of forty-four
documents illustrating ecclesiastical organization and the development of
the missions from 1560 to 1610. Volume III contains a report on general
conditions in Yucatan in 1766 entitled Discurso sobre la constitucion de las
Provincial de Yucatan y Campeche. Included in the volume are two appen-
dices, the first describing the government of Campeche in 1746, the second
being a census of Yucatan for 1790. In the Handbook of Latin American
studies, 1936, pp. 387-432, Dr. Chamberlain published "A report on colonial
materials in the government archives of Guatemala City."

Mr. R. L. Roys devoted the first part of the period under review to re-
vision and completion of maps of the prehistoric Yucatecan Maya states,
or so-called provinces, of the Cupuls, Sotuta, and Mani, from topographical
material gathered during the spring of 1937 and described in a previous
report.1 The first two will appear in The Titles of Ebtun,2 and the last will
accompany the publications of the Xiu probanzas and related documents.

The two series of documents mentioned above constitute a general history,
from the native point of view, from the Spanish Conquest down to the
period covered by the ethnological studies of the modern Maya. These
papers deal principally with the more material facts of existence and may
be supplemented in course of time by a study of native intellectual and
religious life during the colonial period. Some of the material for this will
be found in the mixture of Spanish astrology and Maya science, both of
which were closely bound up with religious ideas, recorded in the Maya lan-
guage in the later Books of Chilam Balam.

At the present time, however, it has seemed desirable to inquire more
closely into what the white man found when he arrived in the various parts
of the Maya area: the state of affairs at the time of this contact, as dis-
tinguished from subsequent developments influenced by European culture,
on one hand, and previous conditions no longer existing but disclosed by
archaeological investigation, on the other.

There are some indications that more or less similar conditions may well
have existed for at least three centuries prior to the Conquest in the high-
lands of Guatemala and perhaps considerably longer in regions between that
area and Yucatan. In Yucatan, however, there was a great political and
social revolution about the middle of the fifteenth century. Its more con-
spicuous effects were the breaking up of a centralized government and the
abandonment of the stone-vaulted buildings, which were replaced by more
or less perishable structures with thatched roofs. In the Old World such a
decline in architecture has been either more gradual or the result of invasion
and immigration by less cultured peoples, which was not the case in Yucatan
at this time. Much of the previous state of affairs, which reminds us in some
respects of the conditions in the highlands of Guatemala at the time of the
Conquest, was still a matter of general knowledge when the Spaniards con-

1Year Book No. 36, p. 23.

2 Carnegie Inst. Wash. Pub. No. 505.

DIVISION OF HISTORICAL RESEARCH 169

quered Yucatan, so it may be possible to trace the causes and effects of this
famous crisis in aboriginal American history.

New documents discovered by Mr. Scholes in the archives of Mexico and
Spain have not only added to the sum of our knowledge, but also required
a fresh examination and reinterpretation by Mr. Roys of historical sources
which have long been known.

For the Report and census of the Indians of Cozumel, 1570, already
mentioned in a previous report1, the introduction has been enlarged and re-
written from the study of a considerable number of related documents
furnished by Mr. Scholes.

An ethnological study has also been made by Mr. Roys of the proceedings
of Landa's inquisition in 1562, which furnishes a very appreciable amount
of new material. In Mr. Roys' opinion, the human sacrifices and other
pagan ceremonies performed in Christian churches during the second decade
after the Conquest suggest that temple ritual had continued to retain much
of its importance, in spite of the decline of temple architecture and the
prominent part played by the private oratory.

Sacrifices were made to bring rain and favorable weather for the crops,
to avoid recurrence of hurricanes, and for the benefit of ailing chiefs. It
is of especial interest to learn that the cenote cult was not confined to
Chichen Itza. While some victims were still taken to that site, in numerous
cases the bodies were cast into local cenotes in the Sotuta district. Although
Christian influences are already seen in the crucifixion of some victims,
a logical development since the cross was a Maya religious symbol, the
details of other forms of sacrifice are invaluable to the ethnologist.

We are introduced here to a new category of Maya deities, the gods of
the different lineages or name groups. The greatest of these, Zacalpuc,
we already know as one of the early Mexican invaders of Yucatan and the
head of a lineage. Indeed, he still figures in the prayers of the modern
native herb doctors.

Now that photographs of the oldest copies of the Pech documents have
been acquired, Mr. Roys has undertaken a new transcription and annotated
translation of these papers. They consist of two collections, one from the
town of Chicxulub and the other from Yaxkukul. These towns formed the
subject of a topographical study2 in 1937. Brinton published the text and
translation of the most important Chicxulub document in 1882, and Martinez
did the same for all the Yaxkukul papers in 1926, but did not include the
official Spanish translation made in 1769.

These important documents are probably the earliest Maya narratives
written in European script that have come down to us and include accounts
of the Spanish Conquest by two native chiefs who were allies of the
Spaniards. In consideration of Dr. Chamberlain's current study of the
conquest of Yucatan and a number of later documents from the Pech area
discovered by Mr. Scholes in the Archives at Seville, the publication of the
entire series of the Chicxulub and Yaxkukul papers with new annotations
seems desirable at this time.

xYear Book No. 33, p. 107.
2 Year Book No. 36, p. 23.

170 CARNEGIE INSTITUTION OF WASHINGTON

SECTION OF THE HISTORY OF SCIENCE 1

Introduction to the History of Science. Notable progress has been made
by Dr. George Sarton in the preparation of volume III, dealing with the
fourteenth century, 152 articles, some of them of considerable length, having
been written. Though the redaction of these articles is now meant to be
final, it is likely — judging from earlier experience — that before the work
is completed, many will require additions and revisions, and that a few may
have to be entirely rewritten. All these notes concern the authors of scien-
tific texts in Latin or in the vernaculars of western Europe.

The end of the Latin and western European part (by far the largest of the
book) is now in sight, and it is hoped that the analytic stage of the whole
work may be completed within the next academic year. This very elaborate
and patient analysis is merely a preparation for the synthesis of fourteenth-
century science and learning which will then be undertaken.

Dr. Welborn has continued to assist Dr. Sarton, checking data and adding
items to the bibliographies. Dr. Pogo has also assisted Dr. Sarton and has
continued his astronomical studies bearing on the problem of the correlation
of Maya and Christian chronologies. His report follows:

Maya astronomy. It becomes increasingly difficult, because of their highly
technical subject matter, to make the annual summaries of this research con-
cise, yet intelligible both to Mayologists and to astronomers. No technical
explanations will be given in the present report. Work on the various aspects
of the correlation problem proceeded slowly, the two principal investiga-
tions being centered on the lunar and the planetary records of the Maya. A
considerable amount of time was devoted to the reading of the proofs of Dr.
Morley's forthcoming Inscriptions of Peten; all the Maya dates and calen-
darial computations found in the work were checked. The appended bibliog-
raphy indicates the progress of the theoretical investigations dealing with
eclipses in general, and of the accumulation of observational data on the
visibility of penumbral lunar eclipses in particular; these studies, necessary
for a deeper insight into the structure of the Maya records preserved in the
Dresden Codex, have yielded results which should be of interest to students
of Mesopotamian-Mediterranean eclipse records.

Scientific incunabula. The publication of Arnold C. Klebs' Incunabula
scientifica et medica {Osiris, vol. 4, pp. 1-360, 1937), a work which had been
in preparation for a great many years, made it possible to undertake a study
which Dr. Sarton has had in mind for a long time but which he had delib-
erately postponed until Klebs' preliminary survey became available. As
Dr. Sarton has frequently stated, it does not suffice to record when, where,
and how a discovery has been made or a scientific treatise written; it is
equally necessary to set forth the tradition of that discovery or of that
treatise, for if the discovery or the treatise had not been transmitted it is
almost the same as if the former had never been made, or as if the latter
had never been composed. • In the history of scientific tradition it is always
important to determine exactly when it first occurred in print, for in most

1 Twentieth animal report for the period from July 1, 1937 to June 30, 1938 (previous
reports appeared in Year Books Nos. 18-36, 1919-1938; the twelfth and following also
appeared in Isis, the latest in vol. 28, pp. 87-91, 1938).

DIVISION OF HISTORICAL RESEARCH 171

cases the printing of a text meant its final salvation for posterity. Thus in
volumes I and II of the Introduction Dr. Sarton has taken pains to indicate
the earliest printed editions of each text dealt with. These earliest editions
are often incunabula, i.e., prints anterior to 1501, and the historian of science,
even if he is not specially interested in rare books as such, is nevertheless
obliged to pay special attention to them.

Though his earliest investigations had led him to the examination of many
incunabula problems, Dr. Sarton had never surveyed incunabula literature
in general. Dr. Klebs' careful list of all the scientific and medical incunabula
has now made it possible for the first time to consider such works as a group,
from the statistical point of view. The results of his investigations will
appear in Osiris (vol. 5) . It is hoped that the studies of Dr. Klebs and those
of Dr. Sarton will encourage other students to prepare careful analyses
and discussions of the contents of incunabula. Thus far these precious
volumes have been treated too much like relics and considered from the
outside only, from the rather low point of view of the collector who cares
for bibliographical rarities rather than for ideas, and treasures his books
but does not read them.

Institute for the history of science. Dr. Sarton has published (in Isis,
vol. 28, pp. 7-17, 1938) a third explanation of the need of such an institute
and has outlined the principles of its organization. It should be noted that
the rooms occupied by the Section of the History of Science of Carnegie
Institution in the Widener Library of Harvard University already constitute,
in a very modest way, such an institute. Many of the so-called institutes
attached to European universities are far more rudimentary. A brief ac-
count of the facilities at present available may not be out of place.

According to a census made in December 1937, these rooms contain 3130
books, 8060 pamphlets (reprints, etc.), and some 40,000 bibliographical cards.

The books and pamphlets are of three kinds with regard to provenance.
Some were bought by Dr. Sarton, others were given to the editor of Isis,
finally 823 were bought by the Carnegie Institution. Of the latter, all but
one were purchased during the period 1930-1937. The largest is naturally
the group of books and pamphlets presented to the editor of Isis, though it
represents only a part of the total number given to him, as many of these
books are surrendered to other scholars who kindly undertake to review
them in Isis.

In its totality this apparatus criticus is probably the richest of its kind
anywhere, but its potential value is enormously increased by the fact that
the rooms housing it are a part of the Harvard University Library or Widener
Library, the largest university library in the world today. The total number
of the books and pamphlets in that library (and departmental libraries con-
nected with it) approaches four millions. These are completely and almost
immediately available to the students using our apparatus. For example,
the Harvard University Library has full sets of almost all the important
scientific and learned periodicals and of the academic serials published
throughout the world. Thanks to the generous cooperation of Harvard
University and of the Carnegie Institution an instrument has been created
which is already very good, and might be excellent if the space available for

172 CARNEGIE INSTITUTION OF WASHINGTON

books, archives, and students were increased, and means provided for its
development and fuller utilization.

The rooms are always occupied by Dr. Sarton, Dr. Welborn, and Frances
Siegel (secretary of the Section) and are often occupied by two or three
other persons, students or scholars. They are used for the seminary in the
history of science and learning in Harvard University, and are becoming
more and more extensively recognized as a center of information for these
studies. All the qualities of an institute are thus brought together, except
stability and permanence.

Many members of the faculty and students, not only of Harvard Univer-
sity but of other colleges, as well as visiting scholars, come to consult our
archives and are generally welcome. In addition, many inquiries are re-
ceived by mail, and efforts are made to satisfy them as fully as possible.

Editing of Isis and Osiris. The "institutional," or pedagogical and normal,
function of this section of Carnegie Institution appears very clearly in its
editorial activities, for the journal Isis centralizes information concerning
the history of science received from everywhere, classifies it, submits it to
criticism, and redistributes it to whomever it may concern.

During the course of last year four numbers of Isis were published (74 to
77) completing volumes 27 and 28, plus volumes 3 and 4 of Osiris, devoted
to the longer memoirs. A total of 2318 pages, 17 plates, 119 figures, con-
taining 59 memoirs, 33 shorter notes, 96 reviews and 1655 bibliographical
items.

It is worth noting that every memoir published in Osiris is the subject
of a separate card printed by the Library of Congress. The same could not
be done of course for Isis, the contents of which are far too abundant.

History of Greek Thought — W. A. Heidel

During the year Dr. Heidel has been chiefly occupied with the history of
Greek mathematics down to 400 B.C., or rather with the attempts made by
various modern scholars to reconstruct the development. All these at-
tempts are highly speculative, as is inevitable, because the available data
are too few and, for the most part, too subject to suspicion. From the rela-
tively few certain data, coupled with vague and discredited tradition that
represents Pythagoras as the creator of Greek mathematics, it is now the
fashion to attribute practically the whole development of the science to the
Pythagoreans, despite the certain fact that most of the known mathematici-
ans of the fifth century were Tonians, who, so far as we can discover, had
no connection with Pythagoreans. Dr. Heidel has written a solicited article
on this subject that should shortly be published in Scientia. Besides this
study he has busied himself intensively with the medical and "Sophistic"
literature of the fifth century, together with the Attic drama, which reflects
the thought of the age. Practically the whole of his discussion of early
Greek science and philosophy is now set forth in a first draft.

MOUNT WILSON OBSERVATORY

Walter S. Adams, Director
Frederick H. Seares, Assistant Director

The number of stmspot groups observed during 1937, amounting to 537,
was the largest since the establishment of the Observatory. It is probable
that the maximum of the spot cycle was reached during the summer of 1937.
The number of groups observed was 285 in the northern hemisphere, and 252
in the southern, the mean latitude of the spot zones being 16?7, or 1?3 higher
than for the maxima of the last two cycles. Of 533 spots observed for
polarity, 333 had regular polarity, 12 irregular, and 188 were unclassified.
These observations have been carried on by Nicholson, Richardson, Hickox,
and Edison Hoge.

Photographs of sunspot spectra in the region 7.6600-7.8850 show many
new spot lines and an interesting reversed Zeeman pattern for the band
lines of calcium hydride near X7025. The separations of these lines are
from one-fourth to one-third those of neighboring atomic lines. The spectra
of several spots have been photographed on successive days as the spots
moved across the sun's disk, and will be used in photometric studies of the
spectrum.

Measurements by Pettit of the energy-curve of the sun over the interval
7.0.5 \i to 7.0.315 \i with a 21-foot concave grating and a quartz photo-
electric amplifier give absorption coefficients, by which energy measure-
ments may be reduced to the continuous spectrum, ranging from 0.9 at
7.0.5 \x to 0.61 near X0.39 \i. The energy-curve thus derived is in indifferent
agreement with the black-body energy-curve.

Spectrograms of four bright chromospheric eruptions taken by Richardson
with brief intervals between successive exposures indicate that the only lines
apparently affected are H and K of calcium and the hydrogen lines of the
Balmer series. Distinct emission can be observed at the positions of the
lines HX^, Hv\, and i70.

An eruptive prominence observed by Hickox on March 20, 1938, reached
the record height of 1,550,000 km, or into the general region of the outer
corona. Its position was within 15° of the north pole of the sun. Analysis
of its motions gave but three successive velocities, 67, 135, and 200 km/sec.
An eruptive prominence observed by Pettit at the McMath-Hulbert Observa-
tory on September 17, 1937, reached a height of 1,000,000 km and showed
velocities of 28, 58, 186, 540, and 728 km/sec. The last two values exceed
the parabolic velocity of escape at the corresponding elevations.

These observations indicate that the time interval within which a change
of velocity can take place may be less than 45 seconds, and also that the
velocity may be a multiple not of the preceding but of the second preceding
value. Some apparent discordances, however, may be explained on the
assumption that a change took place before the observations began. On the
basis of a theoretical investigation Pettit concludes that radiation pressure
from bright chromospheric eruptions cannot account for the observed
velocities.

173

174 CARNEGIE INSTITUTION OF WASHINGTON

An extensive series of visual measurements of the percentage amount of
plane polarization in light diffusely reflected by lunar and terrestrial mate-
rials has been completed by Dr. F. E. Wright, Chairman of the Committee
on Study of the Surface Features of the Moon, and the results are being
prepared for publication. A new alternating- current amplifier of special
design is being used for the study of the polarization of moonlight and sun-
light diffusely reflected by terrestrial substances.

Direct photography during the year has included a series of pictures at
4-second intervals of the total lunar eclipse of May 14, 1938; about 25
negatives of Finsler's comet taken in July and August 1937 by Christie;
and planetary photographs at the coude focus of the 100-inch telescope
obtained on kodachrome film by Dunham.

Trigonometric parallax observations by van Maanen have added nine
stars during the year to the list of those with photographic absolute magni-
tudes fainter than +10. Fourteen stars are now known with absolute magni-
tudes of +15.0 or fainter. The most frequent absolute magnitude among
nearly 100 stars of low luminosity is about +12.

Studies of proper motions have included a comparison by van Maanen
of some of the early photographs of fields in the Selected Areas taken nearly
30 years ago with recent plates of the same fields. Measures indicate that
the probable errors on the early plates are too large to justify their use for
accurate determinations of proper motions. A valuable addition to our
knowledge of the proper motions of certain important classes of stars which
have been under spectroscopic investigation has been made by R. E. Wilson,
who by the use of various recent observations has derived accurate proper
motions for more than 700 objects.

Important progress has been made by Seares and Miss Joyner in the
determination of additional standards of magnitude among stars north of
+80°. The larger number of stars now available should provide plate cor-
rections which may make it possible to include in the reduction some of the
earlier long-exposure photographs.

Final photographic magnitudes to the limit 21 have been completed by
Baade for Selected Area 68, and the photovisual scale in the same area to
magnitude 20 is under investigation. Tests on stars between magnitudes
13 and 17 show that the adopted photographic absorption of the platinum
half-filter used in this work conforms to the international photographic scale.

Stebbins and Whitford have completed a survey of the colors derived from
photoelectric observations of about 1300 B-type stars north of — 40°. In
the case of strongly colored B stars they find that the reddening varies as
^—1 instead of X-4, as would be the case for Rayleigh scattering by small
particles. Measures of the colors of A0 stars within 10° of the north pole
show that the obscuration present is due to material more than 100 but less
than 250 parsecs distant, and produces a mean color excess of about 0.10
magnitude.

Additional photometric investigations have included Christie's measure-
ments of the integrated photographic magnitudes of globular clusters, now
including about 80 objects, and numerous observations of individual stars
by various observers.

MOUNT WILSON OBSERVATORY 175

A statistical study by Stromberg of the mean absolute magnitudes and dis-
persions in magnitude of stars of types G8-K2 and G0-G7, as derived from
trigonometric parallaxes, has been completed. The grouping of the stars
was according to reduced proper motion. The relation between H and M
shows a clear distinction between supergiants, giants, and dwarfs. The
spectroscopic absolute magnitudes have in general been found to be nearly
correct and have a mean error of between 0.5 and 0.6 magnitude. A grouping
of the stars according to spectroscopically determined absolute magnitudes
gave results very similar to those obtained from the grouping based on re-
duced proper motion. A separate study of the dwarf stars of types G0-G7
and G8-K2 indicates that the dispersion in absolute magnitude is apparently
underestimated in the spectroscopic results.

In the field of stellar spectroscopy radial velocities have been determined
and published for 600 stars, mainly of advanced types of spectrum, and
for 70 stars of early type investigated primarily for interstellar lines. Sev-
eral bright stars have been observed for small variations in velocity, and a
series of spectrograms of a Bootis has been used for a determination of the
solar parallax.

The radial-velocity curves of 128 Cepheid variables, of which 105 were
previously unobserved, have been derived and published by Joy, and the
results have been studied statistically. These stars are of great importance
because of their high luminosities, their distribution, and the valuable data
they afford for investigations of solar motion, galactic rotation, and absorp-
tion of light in space.

Two results of interest with the coude spectrographs have been the iden-
tification of many lines of ionized elements in the extreme ultraviolet region
of the spectra of O- and B-type stars by Adams and Dunham, and the
discovery of the double character of a number of lines in the spectra of
a Orionis, a Scorpii and other supergiant M-type stars. The principal
double lines observed are clue to Mn i, Cr i, Ca i, Sr n, and Ba n. All
originate from the ground state of excitation of the neutral or ionized atom.
The lack of symmetry of the components and their character make it im-
probable that the doubling is an effect of reversal.

Observations of variable stars have included many of types Me and Se,
irregular variables, and those of the RV Tauri and RR Lyrse types. W
Canum Venaticorum has been followed in detail. The spectra of SU Ursse
Majoris and X Leonis are practically continuous at maximum of light. The
components of the emission lines of o Ceti photographed with high dispersion
at maximum of light show great changes in relative intensity with phase.

Many of the faint older novae have been photographed during the year
by Humason and Joy. Some show a continuous spectrum with no visible
emission lines, while others have emission present. Their color in all cases
is distinctly blue. The densities of Nova Persei (1901) and Nova Aquilse
(1918) have been calculated on the basis of their measured distances and
the assumption of the temperature of an O-type star and prove to be 220
and 70 times the density of the sun, respectively. A value of 60 times the
sun's density is found for 14 other old novae whose distances are less certain.

Measurements of the intensities of the interstellar lines of calcium and

176 CARNEGIE INSTITUTION OF WASHINGTON

sodium have led Dunham to attempt quantitative determinations of the
numbers of atoms of these elements in interstellar space. The faint inter-
stellar line of neutral calcium at X4226 indicates the presence of approxi-
mately 2500 singly ionized calcium atoms for each neutral atom. About
20 electrons per cubic centimeter are required to maintain the ionization
of calcium at the observed level. On this basis calculation gives the fol-
lowing very tentative values for the total concentration per cubic meter of
space: Electrons, 20,000,000. Atoms, Na, 6; K, 0.2; Ca, 0.1; Ti, 0.001.
Merrill and Sanford have derived a value of 1.6 for the ratio of D2 of
sodium to K of calcium and conclude the presence of about three times as
many atoms of singly ionized calcium as of neutral sodium.

Sanford has succeeded in measuring the components of double inter-
stellar lines in five stars additional to those previously known. In three
cases the total absorption of the components has been determined.

Two probable interstellar lines at A6203.0 and X6263.0 have recently
been discovered by Merrill and O. C. Wilson. Their work also provides
further evidence that the wide, diffuse feature at X4430, originally noted
by Beals and Blanchet, is of interstellar origin.

From an analysis of the radial velocities of Cepheid variables as applied
to galactic rotation Joy has found the following elements: solar orbital
velocity, 296 km/sec; longitude of center of rotation, 326 ?3; radius of
sun's orbit, 10,000 parsecs. The lack of observations of stars in the southern
hemisphere greatly reduces the weight of the solutions. A correction for
space absorption of 0.85 magnitude (photographic) per 1000 parsecs was
derived and applied.

The conclusion of Plaskett and Pearce that interstellar matter shares in
galactic rotation is strongly supported by an extensive study of detached
lines by Merrill and Sanford. For the constants of galactic rotation they
find: lQ = 329° ; A = 14.8 km/sec per 1000 parsecs. The nearer gases give
a somewhat larger value of A than those at greater distances, a result
possibly due to a decrease in the average density of interstellar matter at
distances greater than 1000 parsecs from the sun.

A sharp absorption line of considerable strength at X3888 found by O.
C. Wilson in the spectra of 01 C and 02 Orionis and other stars embedded
in the Orion Nebula is probably to be ascribed to the helium atoms of the
nebula. The line is superposed upon the broad diffuse Ht, absorption charac-
teristic of the stars. Measures indicate a systematic velocity of approach
relative to the emission lines of the nebula, a difference possibly due to the
pressure of radiation from the stars acting upon the helium atoms of the
nebula.

Numerous miscellaneous stellar spectroscopic observations have been in
progress. Among these are included: spectra of R and N stars by Sanford
and of various peculiar spectra by Merrill; a study of the lines of ionized
barium in early-type stars by Miss Burwell; radial velocities of faint stars
of large proper motion by Adams and Joy, who have recently published a
list of 25 stars with velocities exceeding 75 km/sec ; radial-velocity observa-
tions of stars in the Selected Areas by Stromberg; the spectrum of the
white dwarf AC + 70° 8247 by Minkowski, in which microphotometer tracings

MOUNT WILSON OBSERVATORY 177

show extremely wide, shallow absorption features at X4135 and A4475; the
spectrum of a seventeenth-magnitude A-type star in the field of the old
nova B Cassiopeiae by Humason; and the discovery by 0. C. Wilson of a
bright emission line in the wing of H in the spectrum of a Bootis which is
probably due to He. Measurements of microphotometric tracings of stellar
spectra have been continued by Dunham and Miss Carlson and other
members of the staff.

Many remarkable results have attended the continuation of Baade's
photography of obscured regions in the sky through red filters, especially
in the direction of the galactic center. The greater space-penetrating power
of red than of blue light has resulted in many cases in showing vastly
greater numbers of stars, marked differences in the patterns of the obscuring
clouds, and the presence of globular clusters and nebulae hardly visible on
photographs in blue light. For example, NGC 6357, of which only one or
two small wisps appear on ordinary photographs, is found on the red plates
to be an outstanding object rivaling in size the Orion Nebula and Messier 8.
In the course of these observations a variable sky fog which appeared on the
photographs and proved to be a function of zenith distance is provisionally
ascribed to the red auroral lines in the earth's atmosphere. This question
is under investigation.

On photographs taken by Baade in December the preceding half of the
variable nebula NGC 2261 appeared with its usual intensity, but the follow-
ing half was completely obscured. Apparently an obstruction near the ex-
citing star, R Monocerotis, through which the boundary of the illuminated
area very nearly passed, threw a shadow upon the following half of the
nebula. Fragmentary observations in January and February showed that
the "shadow" had moved from west to east at the rate of 0'.'08 per day, hav-
ing lost its straight-line appearance in the interval.

Direct photography of planetary nebulae was continued by Dr. Duncan,
who investigated 15 objects. No new ultraviolet envelopes were found, but
interesting new details were observed in several nebulae. Minkowski ob-
tained numerous spectrograms with the interference spectrograph of the
planetary NGC 6826 and found a distribution of radial velocities such as
might be expected in a nebula rotating around its minor axis.

An extensive program completed by Hubble during the year was that of
obtaining satisfactory photographs with the large reflectors of the 800 extra-
galactic nebulae in the Shapley-Ames catalogue, north of —30° and of photo-
graphic magnitude 12.9 or brighter. This work has required the cooperation
of several observers over a period of years. The collection now includes
about 2000 NGC objects and nearly 1000 given in the IC. The material is
under investigation for sequences of classification, frequencies of various
types, and small-scale distribution of nebulae.

About 60 new short-period Cepheids have been identified in a cooperative
study by Hubble, Baade, and Humason of the four relatively near nebulae
M 31, M 33, NGC 6822, and IC 1613. Long-exposure photographs with the
100-inch reflector were made on each nebula on 10 to 12 successive nights.
The magnitudes are being based upon the scale for very faint stars estab-

178 CARNEGIE INSTITUTION OF WASHINGTON

lished by Baade in Selected Area No. 68. Results have been essentially
completed for the variables in IC 1613.

Spectrographic observations by Humason have included determinations of
apparent velocities and spectral types for 21 extragalactic nebulae. These
consist of members of clusters and groups, and several large, resolved, near-by
nebulae. A spectrogram of NGC 4111, taken with a dispersion double that
previously used on this object, is measurable to a distance of 20" from
the nucleus along the major axis. This dispersion will be used in a study
of the rotation of this nebula and a few others.

For the first time it has been possible during the past year to undertake a
systematic study of those remarkable objects, the supernovas in extragalactic
nebulae, with adequate photometric and spectroscopic apparatus. As distin-
guished from ordinary novae, which are found fairly frequently in extra-
galactic nebulae, supernovas occur but rarely and are of a different order of
magnitude. They represent a release of energy far beyond that of any other
known phenomenon, a luminosity of the order of 109 suns having been at-
tained by one of the two objects recently investigated.

The two supernovae in IC 4182 and NGC 1003 discovered by Dr. Fritz
Zwicky, of the California Institute of Technology, with the 18-inch Schmidt
telescope on Mount Palomar had magnitudes of 8.6 and 12.8 at maximum and
were the brightest recorded since Z Centauri (1895). The supernova in
NGC 1003 was discovered before maximum and that in IC 4182 probably a
few days after maximum. Definitive light-curves were established by Baade
and were found to be similar for the two stars and to follow the normal pat-
tern. The two nebulae are resolved, late-type spirals, with distances, estimated
from their brightest stars, of 0.9 X 106 parsecs for IC 4182 and 1.5 X 108
parsecs for NGC 1003. The corresponding photographic absolute magnitudes
were —16.6 for the supernova in IC 4182 and —13.2 for that in NGC 1003.

About 30 spectrograms of the supernova in IC 4182 were obtained, mainly
by Minkowski, beginning on August 29, 1937, about nine days after maxi-
mum, and 10 spectrograms of that in NGC 1003, beginning on September 11,
1937, about two days before maximum. The spectra of the two stars at
corresponding phases were closely comparable except for minor details, and
differed from those of any other known stars, including ordinary novae.

Wide, partially overlapping emission bands form the recorded portion of
the spectrum between X3700 and M5800. In the blue region the chief feature
was a strong band in the neighborhood of X4600, but some fainter bands were
also present. After the first three weeks a fairly stable pattern developed
which persisted with minor changes throughout the period of the observa-
tions. The entire pattern, however, shifted gradually toward the red, the
displacement amounting in June 1938 to about 100 A for the star in IC 4182,
and in January 1938 to about 70 A for that in NGC 1003.

The behavior of the bands in the red (k > 5000) was very different from
that of the bands in the blue. They varied rapidly, appearing and disappear-
ing somewhat like the emission bands in ordinary novae. In February 1938,
when NGC 1003 could not be observed, two narrow bands, each about 40 A
wide, appeared at ?i6299 and M3359 in the spectrum of the supernova in IC

MOUNT WILSON" OBSERVATORY 179

4182. The stronger band at X6299 was still prominent in June 1938 when all
the other bands in the red had nearly disappeared.

The identification of the emission bands in the spectra is a difficult problem,
especially in view of the red shift. No evidence whatever has been found of
the presence of hydrogen, and at present the only plausible identification is
that of the two narrow red bands with the forbidden lines of 0 i at ?i6300 and
A6364. On the assumption of expanding shells the widths of the individual
bands suggest velocities not exceeding 3000 km/sec.

An extensive study of the spectrum of europium has been completed by
King in the physical laboratory. It includes wave-length measurements
of about 3750 lines between X2100 and ^10165, nearly three times the number
previously known ; their separation into lines of the neutral and the ionized
atom; and their temperature classification from results with the electric
furnace. The hyperfine structure of most of the europium lines and the
great range in their intensities have caused unusual difficulty in the investiga-
tion of this spectrum.

A comparison of his results on europium with the solar spectrum has led
King to identify 20 lines of the neutral atom, all very strong in laboratory
spectra, with faint, unidentified solar lines. As would be expected, the lowest-
temperature (ultimate) lines appear in sunspot spectra and the higher-tem-
perature lines in the spectrum of the solar disk. The only lines in the solar
spectrum previously identified as belonging to neutral atoms of the rare
earths were two lines of ytterbium. The new results have also increased
the number of identified lines of singly ionized europium in the solar spec-
trum from the 5 given in the Revised Rowland Table to 27.

King has also commenced a study of the spectrum of gadolinium, which
should greatly increase the number of lines now known. A preliminary ex-
amination of the spectrograms shows a very definite grouping of the lines
with temperature.

The spectra of a number of elements have been photographed by Ander-
son in the vacuum spark in the region A.4500-^.7000, with the use of two com-
mercial condensers, each of one-half microfarad capacity and 50,000 volts,
which have replaced the former glass-plate condensers. The exposure times
required are immensely longer than for the ultraviolet region, and the de-
formation of the spark terminals has presented a serious problem. Attempts
are being made to overcome these difficulties.

Tests made by Babcock about a year ago showed that the screw of the new
ruling machine was undergoing spontaneous changes of form which made
the construction of a new screw necessary. This has now been cut and the
lapping is under way. Especial attention was given to the selection of the
material and exacting tests were made before this work was begun.

Babcock has undertaken the measurement with a photronic cell of the
luminous efficiency of several gratings ruled at Mount Wilson and elsewhere.
The brightest grating investigated was one ruled at Mount Wilson on specu-
lum metal and subsequently aluminized. It seems probable, however, that
evaporated aluminium ruled directly could be made to return more light
than aluminium superposed on an existing ruling. Gratings can now be ruled
which will return from 50 to 60 per cent of the incident, visible, monochro-

180 CARNEGIE INSTITUTION OF WASHINGTON

matic radiation in one order. An interesting result of these measurements is
the extent of the dependence of the intrinsic brightness of the spectrum in
a given order upon the angle of incidence. In some cases the variation may
be as great as twofold.

The partial reconstruction of two important instruments has been in prog-
ress during a portion of the year. The 60-foot tower telescope, the first in-
strument of this type ever built, is being remodeled to provide for greater
convenience in operation and more constant use. The mountings of the
ccelostat and second flat mirrors are being redesigned, a new drive installed,
and many features added to provide for automatic registration of the sun's
image throughout the day. The mounting of the 10-inch photographic
telescope is also being remodeled and a photovisual objective has been
designed to aid in the photography of objective-prism spectra in the yellow
and red regions.

STAFF

The death on February 21 of Dr. George E. Hale, founder of the Observa-
tory, Director from 1904 to 1923, and Honorary Director from that time
onward, brought to a close a life of remarkable accomplishment in the domain
of American and international science. A brilliant investigator whose dis-
coveries in solar physics marked an epoch in this field of research, his name
will be equally remembered for the many great institutions which he con-
ceived and established, and for the breadth of his outlook upon the progress
of science and its part in human life. In the field of astronomy the Yerkes,
Mount Wilson, and Palomar Observatories, and in national and interna-
tional science the National Research Council and the International Coun-
cil of Scientific Unions form but a part of Dr. Hale's contribution to scien-
tific development and the agencies for dealing with it most effectively. His
wisdom in planning the work of the Mount Wilson Observatory, his appre-
ciation of the importance of astrophysics and of the physical method of at-
tack upon scientific problems, and his constant encouragement of his asso-
ciates to undertake investigations freely and independently with every facil-
ity which he could afford them, were but a few of the many characteristics
which he showed so strongly during the years of his conduct of the Observa-
tory. Finally, no one could be associated with him without acquiring a deep
personal affection for him, based upon his charm, his generosity and modesty,
his enthusiasm, and his great intellectual gifts. The influence of his life will
continue as a cherished heritage at the Observatory.

Two other members of the staff have died during the past year, Dr. Francis
G. Pease on February 7, and Dr. Sinclair Smith on May 18. Dr. Pease was
associated with the Observatory from its foundation, and his contribution
to its work, especially in the design of instruments and in theoretical and
practical optics, was very great. He was largely responsible for the com-
pleted design of the 100-inch telescope and many other major instruments.
A skillful and accurate observer, he is best known for his measurements of
stellar diameters with the interferometer, his collaboration with Dr. Michel-
son in determining the velocity of light, and his admirable work in stellar
and lunar photography.

MOUNT WILSON OBSERVATORY 181

Dr. Smith was associated with the physical laboratory for several years,
where his skill and ingenuity led to many researches of interest. He also
undertook observations in the difficult field of nebular spectroscopy with
excellent success. Together with Dr. Pease, Dr. Smith devoted a large part
of his time during recent years to problems relating to the construction of
the 200-inch telescope, and the loss of both of these able and experienced
designers will be felt severely in connection with this great project. To their
associates at Mount Wilson both members of the staff had endeared them-
selves greatly through their unfailing friendliness and courage, and their
cordial willingness to assist at all times with the valuable technical knowl-
edge at their disposal.

Dr. Walter S. Adams, Director, has attended to the numerous duties relat-
ing to the administration of the Observatory and continued his investigations
in stellar spectroscopy, giving much time to problems best studied with the
aid of high-dispersion spectrograms. Dr. Frederick H. Seares, Assistant
Director, has aided in the administration and continued his editorial super-
vision of the Observatory publications. He has also continued his researches
on standard magnitudes.

Dr. Arthur S. King, Superintendent of the Physical Laboratory, has fin-
ished and brought together his extensive results on the wave lengths and the
temperature classifications of lines of the rare earth europium. Dr. John A.
Anderson has continued to serve as Executive Officer of the 200-inch tele-
scope project. The remainder of his time he has given to laboratory investi-
gation of the vacuum spark. Dr. Edwin Hubble has completed an extensive
observing program devoted to the brighter nebulae and has begun a detailed
analysis of these data. Dr. Walter Baade has given special attention to
photometric problems connected with the two supernovse discovered in extra-
galactic systems by Dr. Fritz Zwicky of the California Institute of Tech-
nology and to a continuation of his program of photographing star clouds
and nebulae with the aid of red filters. Dr. Paul W. Merrill, Dr. Roscoe F.
Sanford, and Dr. Olin C. Wilson have continued their cooperative investiga-
tion of problems relating to interstellar matter besides carrying on many
other studies in stellar spectroscopy. Dr. Seth B. Nicholson has remained in
general charge of solar investigations, and during the year has completed
the revision of the manuscript for the volume "Magnetic observations of
sunspots, 1917-1924." Dr. Edison Pettit has given the greater part of his
time to the study of solar prominences. Three months of the summer of
1937 were spent at the McMath-Hulbert Observatory in observations of this
kind. Mr. Harold D. Babcock has been engaged in the measurement and
study of lines in the infrared solar spectrum and in problems connected with
the ruling machines. Professor Alfred H. Joy, Secretary of the Observatory,
has published his observational results on the radial velocities of Cepheid
variables and has discussed their bearing on the problem of galactic rota-
tion. Dr. Francis G. Pease continued his observations with the 50-foot
interferometer and his work on the 200-inch telescope until his untimely
death on February 7, 1938. Dr. Adriaan van Maanen, as for many years
past, has devoted his time to the measurement of trigonometric parallaxes

182 CARNEGIE INSTITUTION OF WASHINGTON

and of proper motions. Dr. Ralph E. Wilson, who joined the staff of the
Observatory January 1, 1938, has also been occupied with proper motions,
which he has derived for variable stars and for stars of infrequent spectral
type. Dr. Theodore Dunham, Jr., has worked largely with high-dispersion
stellar and solar spectra, and has given much time to problems of instrument
design. Mr. Milton L. Humason has systematically studied the spectra of
old novae, obtained spectrograms for 21 extragalactic nebulae, and begun a
study of the rotation of these nebulae. Dr. Gustaf Stromberg has continued
his observations of the spectra of stars in Selected Areas and his statistical
investigations of stellar luminosity. Dr. Robert S. Richardson has given
his time largely to the study of chromospheric eruptions and has begun a
study of their spectra. Dr. Rudolph Minkowski has continued his spectro-
graphic studies of galactic nebulae and has obtained a notable series of
spectrograms of the two supernovae discovered a year ago. Dr. Sinclair
Smith, engaged mostly with problems of instrument design, was transferred
wholly to the 200-inch telescope project on January 1, 1938. His death
occurred four and one-half months later, on May 18. Mr. William H.
Christie has photographed Finsler's comet and carried on miscellaneous
spectroscopic and photometric observations. Mr. Joseph Hickox has con-
tinued as regular solar observer on Mount Wilson. Mr. Hickox and Mr.
Christie together have given the Friday evening public lectures delivered
regularly at the Auditorium on Mount Wilson. Mr. Edison Hoge has served
as part-time solar observer and carried on the miscellaneous photographic
work of the Observatory.

In the Computing Division Miss Louise Ware has assisted both Dr. Nichol-
son and Dr. 0. C. Wilson in solar and stellar investigations. Mrs. Elizabeth
Sternberg Mulders has continued the preparation and compilation of various
data relating to solar activity. Mr. E. F. Adams has handled part of the
regular compilations of solar data and made measurements and reductions
of solar spectrograms. Miss Mary C. Joyner has collaborated with Dr.
Seares in measurements and computations relating to the extension of the
Polar Sequence. Miss Cora G. Burwell has assisted in various stellar
spectroscopic investigations, especially those of Dr. Merrill, and has studied
the intensities of ionized barium lines in early -type spectra. Miss Myrtle L.
Richmond has continued the measurement and reduction of the records of
ultraviolet solar radiation and done much miscellaneous computing. Miss
Ada M. Brayton and Miss Louise Lowen have aided in many phases of the
stellar spectroscopic work, and Miss Lowen has also assisted Dr. van Maanen
in his work on parallaxes and proper motions. Miss Dorothy J. Carlson
has divided her time between computations for Dr. Dunham and compila-
tions relating to nebulae for Dr. Hubble. Mrs. Mary F. Coffeen, who was
appointed on October 18, 1937, has assisted Mr. Babcock in work on the
infrared solar spectrum. Dr. R. M. Langer served as part-time assistant at
the Solar Laboratory until August 1, 1937. Miss Elizabeth Connor, Li-
brarian, has continued to assist in the editorial work of the Observatory.

Dr. Henry Norris Russell, Research Associate of the Carnegie Institution
and Director of the University Observatory, Princeton, has continued an in-

MOUNT WILSON OBSERVATORY 183

vestigation of the errors of spectroscopic parallaxes. Dr. Joel Stebbins,
Research Associate of the Carnegie Institution and Director of the Wash-
burn Observatory, was in residence at the Observatory from July to October
1937 and again during June 1938, engaged in photoelectric measurements
of early-type stars and other special objects. Dr. Albert E. Whitford aided
in these measurements, partly as National Research Fellow and partly as a
special assistant of the Observatory.

Dr. Fred E. Wright, of the Geophysical Laboratory of the Carnegie Insti-
tution, with the aid of Mr. Hamilton Wright, continued his measurements
of the polarized radiation of the moon during the interval August 4 to Sep-
tember 15, 1937. He arrived again in Pasadena June 21, 1938, in preparation
for systematic photography of the moon's surface throughout an entire luna-
tion. Dr. Frank E. Ross, of the Yerkes Observatory, was in Pasadena from
September 1937 until March 1938, engaged in optical computations and tests
on correcting lenses for the Mount Wilson reflectors and the 200-inch tele-
scope. Dr. John C. Duncan, Director of the Whitin Observatory, made ob-
servations with the 60-inch and 100-inch reflectors between July 3 and
August 26, 1937. Dr. Walter T. Whitney, of Pomona College, has served
as volunteer observer at intervals throughout the year, devoting his time to
photometric questions. Dr. Robert King, of the Massachusetts Institute
of Technology, worked in the Physical Laboratory during the summer of
1937. Dr. Lyman Spitzer, Jr., of Princeton University, also spent the
summer at the Observatory, engaged in studies of microphotometer records
of spectra. Mr. Raymond Wilson arrived at Mount Wilson in June for work
as volunteer assistant with the 50-foot interferometer. Mr. William Miller,
of Paramount Pictures, Inc., has served as a volunteer observing assistant
for Dr. Merrill. Mrs. Charlotte Moore Sitterly spent two weeks at the Ob-
servatory in August 1937 in discussions with Mr. Babcock relating to the
infrared solar spectrum. The Observatory has also been visited by many
others with whom the members of its staff have had profitable discussions,
among them, Dr. J. A. Fleming and Dr. A. G. McNish of the Department of
Terrestrial Magnetism, Dr. Ejnar Hertzsprung, Director of the Observatory
at Leiden, Dr. Knut Lundmark, Director of the Observatory at Lund, Dr.
R. W. Wood of Johns Hopkins University, and Dr. E. A. Kreiken from
Sumatra.

Dr. Adams, Dr. Nicholson, and Dr. Dunham attended the annual meeting
and exhibit of the Carnegie Institution at Washington in December 1937.
Dr. Nicholson and Dr. Dunham had the chief responsibility for the prepara-
tion of the exhibit from the Observatory. Dr. Dunham delivered the In-
stitution lecture given regularly on the occasion of the annual meeting. Dr.
Seares delivered, in Washington, on April 19, 1938, the fourth of the Elihu
Root lectures, given under the auspices of the Carnegie Institution. At
various dates in June and July 1938, Messrs. Adams, Baade, Humason, Mer-
rill, Stebbins, Stromberg, and van Maanen left Pasadena to attend the meet-
ing of the International Astronomical Union to be held at Stockholm on
August 3-10. Dr. Russell, already abroad, was also planning to attend the
meeting.

184

CARNEGIE INSTITUTION OF WASHINGTON

OBSERVING CONDITIONS

The number of observing nights during the year was a little below the 25-
year average. The winter was mild, with a minimum temperature of 19° F
on February 13, 1938, and a total snowfall of only 15.5 inches. The maxi-
mum temperature, 97° F, occurred on August 19, 1937. The total precipita-
tion of 58.88 inches replaces last year's total of 53.35 as the second highest
seasonal total recorded for Mount Wilson, and closely approaches the highest,
60.51 inches for 1921-1922. The seasonal average for 34 years is 32.94 inches.
The meteorological event of the year was the rainstorm extending over the
last two days of February and the first three of March 1938. The precipita-
tion, including a half-inch of snow on the last day, was 26.23 inches, 45 per
cent of the total for the season. The storm set a record for a 24-hour interval :
12.81 inches, from 9 p.m. March 1 to 9 p.m. March 2. The Angeles Crest
Highway leading to Mount Wilson was carried away in a dozen places and
at many other points was blocked by slides. About two weeks were required
for temporary repairs sufficient to permit emergency motor travel to the sum-
mit. The road was closed to the public for three months during the exten-
sive reconstruction required.

During the year July 1, 1937, to June 30, 1938, stellar observations were
made on 281 nights, of which 208 were wholly clear and 73 partly cloudy;
solar observations were made on 293 days. The accompanying table shows
the distribution of nights during which observations were made with the 60-
inch reflector.

Observations

Month

Observations

Month

All
night

Part of
night

None

All
night

Part of
night

None

1937:

July

August

September

October

November

December

27
30
25
22
15
15

2
1
4
7
12
8

2
0
1
2
3
8

1938:

January

February

March

April

May

June

Total

Mean 25 years. .

12
7
5
5
4
6

208
204

84
75

SOLAR RESEARCH

The routine program of daily observations of sunspots, prominences, and
flocculi and the daily records of the intensity of ultraviolet radiation and
of the direction and horizontal intensity of the earth's magnetic field have
been continued.

Daily photographs of the sun have been sent semimonthly to the Naval
Observatory to complete their record of the positions and areas of sunspots,
which is published in the Monthly Weather Review. Reports of the daily
number of sunspots and groups have been communicated weekly to Science

MOUNT WILSON OBSERVATORY 185

Service at Washington for publication in their bulletins of Cosmic Data.
Duplicate spectroheliograms have been supplied regularly to the Kodaikanal
and Meudon observatories as a part of the plan of cooperative solar observa-
tion. The approximate positions, field strengths, and magnetic classifications
of all sunspots have been printed regularly in the Publications of the Astro-
nomical Society of the Pacific. Estimates of daily character figures of solar
activity from calcium and hydrogen flocculi have been sent to Commission
10 of the I. A. U. for publication in its Bulletin for Character Figures of
Solar Phenomena. These estimates have also been published in Terrestrial
Magnetism and Atmospheric Electricity. The data were compiled and pre-
pared by Nicholson and Mrs. Mulders.

The positions and intensities of bright chromospheric eruptions have been
communicated by Richardson to Commission 11 of the I. A. U. for publica-
tion in the Bulletin for Character Figures as a part of the cooperative pro-
gram of solar observation with the spectrohelioscope.

Measurements of ultraviolet radiation by Pettit and Miss Richmond have
also been published regularly in this Bulletin.

Estimates of the daily magnetic character figures have been made by E. F.
Adams for publication in Terrestrial Magnetism and Atmospheric Electricity.

The year has seen the completion of an investigation of long standing
by Hale and Nicholson, "Magnetic observations of sunspots, 1917-1924,"
a quarto volume in two parts, to be issued as Carnegie Institution Publica-
tion No. 498. The manuscript went to the printer in April 1938.

SOLAR PHOTOGRAPHY

Solar photographs have been made by Hickox, Hoge, Nicholson, and
Richardson on 268 days at the 60-foot tower telescope. Direct solar pho-
tographs are usually taken early in the morning and followed by spectro-
heliograms made at the 60-foot, the 18-foot, or the 7-foot focus, according
to the quality of the seeing. The spectroheliograms with the 7-foot focus
objective are on motion-picture film used in an automatic recorder, which
is easily exchangeable with the plateholders and runs continuously unless
larger spectroheliograms are being made or the spectrohelioscope is in use.
The exposures are of from one to two minutes duration, separated by inter-
vals of from one to two minutes ; and within these limits the sun was under
observation for an average of 6 hours on 268 days during the year. The
approximate number of exposures of each kind was as follows:

Direct photographs 590

Ha spectroheliograms of spot groups, 60-foot focus 440

Ha spectroheliograms, 18-foot focus 1,500

Ha spectroheliograms, 7-foot focus 28,000

K2 spectroheliograms, 18-foot focus 770

K prominences, 18-foot focus 870

SUNSPOT ACTIVITY

During the calendar year 1937, solar observations were made on 314 days,
on all of which spots were visible. The monthly means of the number of
groups observed daily during the past two and one-half years are given in
the accompanying table.

186

CARNEGIE INSTITUTION OF WASHINGTON

Month

January .
February-
March. . .
April. . . .

May

June

Daily number

1936

5.6

7.7
7.9
8.4
6.3
7.1

1937

10.7
12.0
9.5
8.3
8.6
9.8

1938

9.7
7.0
8.7
11.3
9.1

Month

July

August

September

October

November

December

Yearly average

Daily number

1936

11.2

7.7

1937

13.6

12.0

9.1

10.0

7.8

7.9

9.9

The mean number of groups observed daily in July 1937, namely 13.6,
exceeded that in any month of the last two cycles. The number of groups
in the northern hemisphere increased from 226 in 1936 to 285 in 1937 ; in the
southern hemisphere, from 233 to 252. The total number of groups, 537, ob-
served here in 1937 established a new record for Mount Wilson: 459 groups
were observed in 1936, 450 in 1917, and 424 in 1927. The exact time of
maximum activity cannot yet be stated with certainty, but it is unlikely
that the activity in this cycle will exceed that of July and August 1937. The
mean latitude of spot zones was 16 ?7, 1?3 higher than for the maxima of
the last two cycles. The largest groups of the year, Nos. 5477 and 5578,
which crossed the central meridian on July 28 and October 4, 1937, respec-
tively, were among the six largest groups ever observed.

SUNSPOT POLARITIES

When possible, the magnetic polarities in each spot group have been ob-
served at least once. The accompanying table indicates the number of spot
groups classified from July 1937 to July 1938. "Regular" groups in the
northern hemisphere are those in which the preceding spot has N (north-
seeking) polarity and the following spot S polarity. In the southern hemi-
sphere the polarities are reversed.

Hemisphere

Polarity

Regular

Irregular

Unclassified

North

163
170

4
8

South

Whole sun

333

188

SUNSPOT AND SOLAR SPECTRA

Nicholson, Hoge, and Hickox have photographed the sunspot spectrum
from M)600 to X8850 with the 75-foot spectrograph at the 150-foot tower
telescope through polarizing apparatus suitable for the study of Zeeman dis-
placements. Many new spot lines are recorded on these spectrograms. The
band lines of calcium hydride near A7025 were found to have reversed Zee-

MOUNT WILSON OBSERVATORY 187

man patterns, with separations from one-fourth to one-third those of atomic
lines in the same region. The lines in the primary band of titanium oxide at
X7054 have normal Zeeman patterns with displacements of the same magni-
tude as those of the calcium hydride lines.

Spectrograms of several large stable sunspots have been obtained by Rich-
ardson at the 150-foot tower for use in the photometry of the spot spectrum.
Four selected regions were photographed on successive days, when the ob-
serving conditions were excellent, as the spot moved from the east to the
west limb. Much information concerning the structure of sunspots may be
obtained from spot spectrograms taken in this way. The plates have not
yet been measured.

The faintness of rare-earth lines in the solar spectrum is well known, and
most of those hitherto identified belong to the ionized atom. With the aid
of his recent laboratory data on europium (see pp. 204—205), King has been
able to identify more than 20 of the neutral lines of this element with faint
solar lines and to increase the known singly ionized europium lines in the
sun from 5 to 27.

INFRARED SPECTRUM OF THE SOLAR DISK

Study of the spectrograms on hand has been completed by Babcock and
specifications for the plates still required have been determined. The reduc-
tion of the spectrograms has been shortened by using tables of the coefficients
appearing in the formulae. The equipment in the Government Building used
for most of the observations has been of great service, but the lack of a tele-
scope imposed serious limitations. Transfer of the work to the Hale Solar
Laboratory has therefore given it fresh impetus.

The 150-foot focus arrangement of the excellent reflecting telescope at the
Laboratory has been put into commission, and the 75-foot spectrograph has
been arranged to obtain the spectrograms of the center and the limb of the
disk that are so much needed. The 21 -foot concave grating formerly used
in the Government Building has been remounted at the Solar Laboratory in
a modified Eagle arrangement, where it may be used with any of the solar
images provided by the telescope. Preliminary observations with this ap-
paratus, now nearly in final form, indicate a satisfactory efficiency.

ULTRAVIOLET ENERGY-CURVE OF THE CONTINUOUS SOLAR SPECTRUM

The energy-curve of the sun has been measured by Pettit with the 21-foot
concave grating and a quartz photoelectric amplifier over the interval
X0.5 fx to 0.315 \i in steps of 0.1 \i. The area under an intensity-curve divided
by the area under a line drawn through the point of highest deflection gives
the absorption coefficient of the solar spectrum with which energy measure-
ments made thermoelectrically may be reduced to the continuous spectrum.
The values range from 0.9 at X0.5 \x to 0.61 near X0.39 \i. Correction with
the aid of these ratios modifies the form of the energy-curve but does not
greatly improve its agreement with the black-body energy-curve.

CHROMOSPHERIC ERUPTIONS

Arrangements to photograph the spectra of bright eruptions in the chromo-
sphere with the 60-foot tower telescope have been made by Richardson. The
sun is kept under observation with the spectrohelioscope. When an eruption

188 CARNEGIE INSTITUTION OF WASHINGTON

starts, the spot is identified and the beam transferred to a mirror system
that gives a 7-inch image. Exposures are then made at intervals of a few
seconds in the second order of a concave-grating spectrograph.

Four eruptions of intensity 1 or 2 have thus far been observed on the
disk, and their spectra have been photographed from X6600 to ^,3400. The
only lines apparently affected on these exposures are the Balmer series and
the H and K lines of calcium. Emission can be distinctly seen in H^, Hr\,
and HQ. None of these hydrogen lines has been definitely identified in the
normal solar spectrum. The intensity of the emission from Ha to Hs, in-
clusive, is very nearly the same as that of the continuous spectrum near the
lines.

ERUPTIVE PROMINENCES

An eruptive prominence observed by Hickox on March 20, 1938, rose in
2h34m to the record height of 1,550,000 km, or 1.12 solar diameters, thus show-
ing definitely that prominence material may reach the regions of the outer
corona. The prominence appeared within 15° of the north pole of the sun,
an unusual location for these objects. Analysis of the motions gave only
three successive velocities, 67, 135, and 200 km/sec.

Pettit spent three months of the summer of 1937 at the McMath-Hulbert
Observatory, collaborating with Mr. R. R. McMath in the study of promi-
nences. Seven eruptive prominences were observed with the motion-picture
equipment, making a total of 9 for the observing year, the largest number
ever observed; the average for 50 years is one per year. The prominence
observed at Lake Angelus on September 17, 1937, rose to a height of 1,000,000
km, with velocities of 28, 58, 186, 540, and 728 km/sec. The last two values
exceed the parabolic velocity at the corresponding elevations and are the
highest yet observed in prominences. The observations of this prominence
reduce the time interval required for a velocity-change from the previous
estimate of 5 or 10 minutes to less than 45 seconds.

The first law of motion of eruptive prominences is now abundantly verified.
The second law, that any velocity is a small multiple of the preceding veloc-
ity, must be modified, however; occasionally a velocity is a multiple not of
the preceding but of the second preceding value. Some apparent discordances
can thus be explained on the assumption that in certain cases a change of
velocity occurred before observations began.

Pettit has shown that, because of the Milne effect, we cannot assume a bal-
ance of light-pressure and gravity. With an initial velocity of 10 km/sec,
a value very common in quiescent prominences, high velocities would develop
in a few minutes ; hydrogen and ionized calcium would tend to separate ; and
the character of the motion would be unlike that observed. As a propellant,
radiation pressure from bright chromospheric eruptions seems to be an im-
possibility.

PHENOMENA OF PROMINENCES

Continuous observation of an active prominence over a considerable period
occasionally reveals faint streamers, unconnected with the prominence, enter-
ing the center of attraction from high up in the coronal region with velocities
of about 150 km/sec. About a dozen of these "coronal" prominences have
been observed at Lake Angelus and five have been measured in detail.

MOUNT WILSON OBSERVATORY 189

Over an active sunspot group small, nearly round masses of chromospheric
matter occasionally shoot out and, unlike the surges, do not return. These
"ejections" are usually very faint, many being at the limit of vision on the
films. Aside from surges and ejections, all motions in sunspot prominences
are downward to the spot.

Ordinarily, streamer formations above a sunspot are preceded by the ap-
pearance of a bright, nearly round cloud, which feeds the streamers extend-
ing from one side of the cloud to the spot area. Sometimes the cloud elon-
gates and feeds streamers from both ends, the prominence matter moving
down both branches of the loop. Such loop formations are frequently seen
over sunspot groups (class Illb prominences). Measures of 94 streamers
in active and sunspot prominences continue to show that the first, and in
many cases the second, law of prominence motion applies.

LUNAR AND PLANETARY INVESTIGATIONS

SURFACE FEATURES OF THE MOON

Dr. F. E. Wright, Chairman of the Committee on Study of the Surface
Features of the Moon, has completed the series of visual measurements of
the percentage amount of plane polarization in light diffusely reflected by
lunar and terrestrial materials and is now preparing the report on the results.
To study the polarization of moonlight and of sunlight diffusely reflected by
terrestrial substances, a new high-gain, alternating-current amplifier has
been constructed in the laboratory of the Department of Terrestrial Magne-
tism from designs by Mr. Ellis Johnson of that Department. The instru-
ment is used with a rotating Nicol prism (10 cycles per second) and furnishes
an independent check on visual measurements. Preliminary tests indicate
that it operates satisfactorily and has adequate sensitivity for the measure-
ment of the intensity of the polarized component of the incoming beam; it
also measures the total intensity of the incoming beam, but with smaller
precision.

Dr. Wright is planning to photograph the lunar surface at brief intervals
throughout the full lunation beginning June 27, 1938. The photographs will
be made at the Newtonian focus of the 100-inch reflector with the aid of a
zero corrector, which functions extremely well over the spectral range X5000-
M5000, and will form the basis for a topographic reconnaissance map of the
central portion of the moon.

MOTION PICTURE OF LUNAR ECLIPSE

With the cooperation of Paramount Pictures, Inc., who supplied the camera,
film, and processing, Christie and Mr. William Miller photographed the
moon at 4-second intervals during the total lunar eclipse of May 14, 1938.
The exposures, ranging from 0.02 to 2 seconds, were made with the 10-inch
Cooke refractor, which gives a satisfactory scale for projection.

FINSLER'S COMET

Finsler's comet, whenever visible during July and August 1937, was photo-
graphed by Christie with the 10-inch telescope. The series of about 25
negatives shows the rapid changes in the form and the structure of the tail
now recognized as characteristic of comets when close to the sun.

190

CARNEGIE INSTITUTION OF WASHINGTON

PLANETARY PHOTOGRAPHY

Dunham has continued his experiments in planetary photography at the
250-foot coude focus of the 100-inch reflector mentioned in last year's report.
Kodachrome film has been used to obtain photographs in color.

MISCELLANEOUS STELLAR INVESTIGATIONS

TRIGONOMETRIC PARALLAXES

As for several years past, van Maanen has concentrated his parallax work
largely on stars suspected of having very faint absolute magnitudes. Dur-
ing the year nine stars have been added to the list for which the photographic
M is fainter than +10. One of these, vM,W No. 112, has M= + 15.0. Of
the 116 stars supposedly of low luminosity which are now finished, 5 have
given negative parallaxes and 15 are companions. Omitting these, van
Maanen finds the distribution of absolute magnitudes to be as shown in the
accompanying table.

Photographic M

No. stars

Photographic M

No. stars

< +9.0

13.0-13.9

14.0-14.9

15.0-15.9

^ +16.0

9.0- 9.9

10.0-10.9

11.0-11.9

12.0-12.9

Including vM,W No. 112, we now know 14 stars with photographic ab-
solute magnitude equal to or fainter than +15.0; three of these are com-
panions.

An absolute parallax of — 0'/012 has been found for SS Cygni. Since
last year's report gave +0'/010 for U Geminorum, it seems doubtful if stars
of this type of variability can be considered as dwarfs, as has been suggested
by Parenago and Kukarkin (V. F. A., Gorki, vol. 4, p. 249, 1934).

PROPER MOTIONS

Four Selected Areas, Nos. 60, 72, 91, and 92, have been measured by van
Maanen for proper motion. In addition, No. 35 had been measured before.
For each field two early exposures, made by Seares for his photometric work,
were compared with two exposures taken recently at the Newtonian focus
of the 60-inch reflector. The results of the measures of these five fields are
as follows:

The probable errors of a final \ia, \is, and \i for a star are 0"0029, 0"0028,
and 0"0038, respectively, while for the 13 nebulae shown with good measur-
able images the errors are about twice as large. Since the mean motions of
the fainter stars in a galactic latitude equal to the mean for the five fields
may be expected to be O'/OIO to 0'/015, it is evident from the probable errors
alone that the available material hardly warrants a major undertaking of
measuring some 30,000 to 40,000 stars in the 135 Selected Areas for which
early plates are available. For a possible reduction of the relative motions
of the nebulae and the fainter stars, the results are even less promising owing

MOUNT WILSON OBSERVATORY 191

to the small number of the nebulse measurable on these plates and their rela-
tively large probable errors.

Analysis of the motions according to magnitude and amount of proper
motion shows further that the percentage of small motions (<0'/010) is only
half of that found by Willis from a series of plates taken at the Cassegrain
focus of the 60-inch reflector. This indicates that the probable errors in the
measures of plates taken at the Newtonian focus are too large for these
plates to be of great use. Finally, an attempt to derive the direction and the
amount of parallactic motion for these faint stars gives no reliable result.

The main cause for these disappointing results is probably the fact that
the early plates were not taken with astrometric measures in view. The hour
angles are large, in the mean 27° (30° for the five fields measured) , and many
of the plates are not of the quality required for such measures.

Boss's General Catalogue gives proper motions of stars of the more common
spectral types in sufficient numbers to permit good determinations of the
motions and mean absolute magnitudes for these types. For types Me, N, R,
and S and for variable stars of all classes, on the other hand, the proper
motions are not numerous, especially among the brighter stars for which
early meridian-circle observations are available. It is desirable therefore
that special effort be made to determine the motions of these stars, and since
the motions are generally small, they should be determined with the greatest
accuracy possible. R. E. Wilson has utilized for this purpose special lists
of positions observed in recent years, notably at Lund and at Lyon, and the
Yale Zone Catalogue, none of which was used in preparing the General
Catalogue. Proper motions and new positions for 1950 were thus found for
382 stars. With these results, and the data in the General Catalogue and
others determined photographically, more than 700 proper motions are now
available for these special classes of stars.

PHOTOMETRIC EXTENSION OF THE POLAR SEQUENCE

Work on the magnitudes of stars north of +80°, undertaken jointly with
Dr. Ross of the Yerkes Observatory, has been continued by Seares and Miss
Joyner. The additional series of photo visual plates centered at 85° re-
ferred to in last year's report has been completely reduced, and the results
have been included in the mean magnitudes. The great majority of the
means are of ample precision for use as supplementary standards, but in the
lower zones of declination there is still some weakness. With the larger
number of stars now available for the determination of plate corrections, it
is hoped that some of the long-exposure photographs centered at 83°, which
originally gave trouble, can now be included in the reduction.

FAINT PHOTOMETRIC STANDARDS IN SELECTED AREAS

As mentioned in last year's report, the platinum half-filter method has been
adopted by Baade for the extension of the photographic scale in a limited
number of Selected Areas to magnitude 21. The present half -filter has been
carefully investigated with regard to homogeneity and absorption constant.
Tests on stars between magnitudes 13 and 17 in a number of Selected Areas
show that the adopted photographic absorption constant of the filter con-
forms with the international photographic scale. Final photographic magni-

192 CARNEGIE INSTITUTION OF WASHINGTON

tudes to the limit 21 are now available for Area 68. Since the new 3-com-
ponent zero corrector for the 100-inch telescope is now ready, the work on
the remaining Areas should progress rapidly. In addition, the establishment
of the photovisual scale down to magnitude 20 has already been started in
Area 68.

COLORS OF B- AND A-TYPE STARS

Stebbins and Whitford have completed a survey of photoelectric colors for
about 1300 B-type stars, including most of the BO and B2 stars north of
declination — 40° and brighter than the limit of the Draper Catalogue. The
reduction of the observations made at Madison and Mount Wilson to a com-
mon system is about finished, and the material is ready for a definitive
discussion.

Stebbins and Whitford have also applied a photocell to the spectro-
photometry of strongly colored B stars and find that the reddening varies
as A.-1, and not as X-4, as would be the case if the absorption were Rayleigh
scattering by small particles in space. From the colors of A0 stars within
10° of the north pole, they find that the obscuration about the pole is due to
material more than 100 but less than 250 parsecs distant, causing a mean
color excess of about 0.10 magnitude on the international scale.

GLOBULAR CLUSTERS

Christie's program for the measurement of integrated photographic magni-
tudes of globular clusters reported in 1935-1936 has been extended to include
about 80 objects. Except for a few polar comparison photographs that must
be obtained at a season when observing conditions are likely to be poor, the
observations are complete. Baade's photographs of clusters through red
filters, which penetrate much of the obscuring material scattered along the
galactic plane, are described on page 201.

SKY PATROL

An experimental monthly patrol, covering as much of the sky as possible,
has been finished by Christie. The exposures of 15 minutes, made with a
large-field lens of 2 inches aperture, reached the tenth magnitude and were
intended for the record of unexpected novae, comets, etc.

MINIMUM BRIGHTNESS OF WW CYGNI

At the request of Dr. Dugan of the Princeton Observatory, Baade observed
the minimum of the eclipsing variable WW Cygni with the 100-inch reflector
on J.D. 2428838.73. Dugan's suspicion that at minimum the variable might
disappear completely was not confirmed. The minimum photographic mag-
nitude was only 13.9.

STATISTICAL STUDIES

Stromberg has continued his work on theoretical and practical investiga-
tions in stellar statistics. The new method reported last year for determin-
Service at Washington for publication in their bulletins of Cosmic Data.
parallaxes, the stars being grouped according to the reduced proper motion
H(H = m + 5 log \i) , has been extended and applied to other spectral types
for which sufficient data are available. For stars of types G8-K2, and to
a less extent for G0-G7 stars, the relation between H and M shows a clear

MOUNT WILSON OBSERVATORY 193

distinction between supergiants, giants, and dwarfs. The spectroscopic
absolute magnitudes have in general been found to require no systematic cor-
rection and to have a mean error between 0.5 and 0.6 magnitude. The small
dispersion in absolute magnitude among the normal giants of spectral types
G8-K2 has been confirmed.

The stars were also grouped according to spectroscopically determined
absolute magnitudes, giving a regression line defining the statistical rela-
tion between the spectroscopic and the true mean absolute magnitude. Com-
parison of results derived with this method of grouping with results from the
grouping according to H shows that the difference between the "impartial-
relation line" and the regression line is not very large for these spectral
classes.

The dwarfs of types G0-G7 and G8-K2 have been studied separately.
This study shows that the dispersion among the dwarfs has apparently been
somewhat underestimated. This effect has been found to be due partly to
the use of regression-curves, and partly to errors in the general slope of the
reduction-curves.

STELLAR SPECTROSCOPY

Stellar spectroscopic investigations during the year have covered a wide
field extending from the study of the brightest stars with high dispersion to
observations of supernovse and other extremely faint stars with low dispersion
and cameras of very short focus. The coude spectrograph in its two prin-
cipal forms with focal lengths of 9 feet and of 32 inches, respectively, has
been used extensively for observations of stars of magnitude 6.5 or brighter.
With its aluminized Wood grating, exceptionally bright in the red of the first
order and the violet and ultraviolet of the second order, this instrument has
been exceedingly valuable for investigations in which high resolving power
and good focus over a large extent of spectrum are essential. For studies of
the H and K lines and of stars with spectra of early type, the 3-prism spec-
trograph with the photographic plate centered at about MIOO has been used
chiefly. A new camera lens with an aperture of 2 inches and a focal length
of 6 inches increases the possibilities of observing faint stars with this instru-
ment, and the spectral types and radial velocities of the fainter stars in the
Selected Areas will be determined with its aid. The 1-prism Cassegrain
spectrograph has been most useful in observations of faint stars of large
proper motion and variables of different types, while the plane-grating
spectrograph at the Cassegrain focus of the 100-inch telescope has provided
excellent material for the study of the D lines and the yellow and red regions
of stellar spectra. For observations of the faintest stars the small spec-
trograph used for nebular investigations and the 2-prism instrument with
collimating mirror and short-focus cameras have been found adequate in
nearly all cases.

The stars under investigation have included an extensive list between
magnitudes 6.0 and 7.5, selected on the basis of apparent magnitude; a
shorter list, selected on the basis of large proper motion, with apparent
magnitudes ranging as low as 12.5; probable and possible members of the

194 CARNEGIE INSTITUTION OF WASHINGTON

Taurus cluster, as selected by Hertzsprung, mainly of magnitudes between
8.0 and 9.5; faint variables; many 0- and B-type stars with interstellar
calcium and sodium lines; stars in the Selected Areas; and most of the
brighter stars which can be photographed with very high dispersion. A total
of nearly 1100 spectrograms has been obtained with the seven spectrographs
in regular use.

RADIAL VELOCITIES

A catalogue of the radial velocities of 600 stars measured during recent
years has been assembled and made ready for publication by O. C. Wilson
and Christie. The stars are mainly those of the general observing program
with magnitudes between 6 and 8 and spectral types F to M, together with
a few fainter stars. The list also includes 69 new spectroscopic binaries.
The spectrograms upon which the results are based were obtained through
the cooperation of most of the members of the stellar spectroscopic depart-
ment.

The radial velocities of about 70 stars of early type, with hitherto un-
determined velocities, have been published by Merrill and Sanford. The
results were obtained in the course of their survey of stars with interstellar
lines in their spectra. Five new spectroscopic binaries were discovered in
the course of the investigation.

High-dispersion photographs of the spectra of a Bootis, a Lyrse, and y
Cygni, obtained in the second order of the 9-foot coude spectrograph, have
been measured by Adams and Miss Lowen for possible variations in the
radial velocities of these bright stars. The results so far accumulated indi-
cate that any such variation must be very small, although additional ob-
servations are required for a Lyrse and y Cygni to make the conclusion certain.

A series of 19 observations of a Bootis taken throughout the year has
been used by Adams in a preliminary determination of the solar parallax.
The study indicates that a relatively small number of observations, made
at suitable times and with all possible instrumental precautions, is capable
of yielding a value of the parallax quite comparable in accuracy with values
derived from extensive astrometric measurements.

The velocities of several spectroscopic binaries and eclipsing stars were
observed by Christie, Joy, Karr, and Sanford ; among them were (3 Capricorni,
Boss 1074, Boss 3303-4, V Cephei, WW Draconis, W Serpentis, VV Cephei,
X, Aurigse, and certain late-type binaries with long period.

RADIAL VELOCITIES OF CEPHEID VARIABLES

An extensive spectrographic investigation of the radial velocities of hitherto
unobserved variable stars of the 5 Cephei type has been published by Joy.
Nearly all stars of this type brighter than the fourteenth magnitude and north
of declination — 40° are included. Velocity-curves are given for 106 varia-
bles. For 22 additional stars scattered velocities were obtained from which
normal velocities were estimated. The velocity- and light-curves were com-
pared, and the relationships between period, lag of the velocity-curve, range
of velocity and light, and form of the curves were studied statistically.

Knowledge of the spectra and the velocities of Cepheids is particularly
important from the standpoint of the constitution and internal activities of

MOUNT WILSON OBSERVATORY 195

stars of high luminosity ; and, on account of the great distance of these stars
and their concentration near the plane of the galaxy, they are a valuable
source of data for investigations of solar motion, galactic rotation, and ab-
sorption in space.

ULTRAVIOLET SPECTRA OF EARLY-TYPE STARS

The spectra of several stars of types 0 and B, photographed with the 32-
inch Schmidt camera and grating and the 9-foot quartz spectrograph at the
coude focus of the 100-inch telescope, have been measured by Adams and
Dunham in the far ultraviolet region ; and, so far as possible, the absorption
lines have been identified. In the O-type stars the principal lines between
>.3020 and X3400 are due to 0 in, Si in, Si iv, S iv, He n, and Ne n ; in the
B-type stars, to 0 n, Si in, S in, He i, and Ne n. The difference in degree
of ionization in the two types is thus well shown by the results. A few promi-
nent unidentified lines were also measured. In the course of the investiga-
tion the wave lengths of the interstellar lines between X3300 and X4300 in
the spectrum of 55 Cygni were determined.

The spectrum of (3 Orionis in the far ultraviolet shows great numbers of
lines, most of which are due to ionized Fe, Cr, and Ti.

SPECTRA OF GIANT M-TYPE STARS

Reference was made in the last annual report to the discovery by Adams
of the double character of a number of lines originating from the ground state
of excitation of atoms of neutral and ionized elements in the spectra of a Orio-
nis and a Scorpii. These observations have been continued with the 9-foot
grating spectrograph and extended to additional stars. The effect is much
more conspicuous in supergiant stars than in ordinary giants and is best
illustrated in the spectrum of a Orionis. In this star the Mn i triplet near
A4030 consists of three pairs of double lines, in each of which the separation
is between 0.3 and 0.4 A. The violet component is much the stronger and
is relatively narrow and well defined. The Cr i triplet beginning with X4254,
the Sr ii pair M4077 and 4215, the Ba n pair U4554 and 4934, Ca i M226, and
a few other lines show similar behavior, although the relative intensities and
the separations of the components for the different elements vary consider-
ably.

Measures of the strong violet component and the weaker diffuse red com-
ponent show that in each case the mean of the two agrees closely with the
normal position of the line. This result suggests a reversal effect; but the
appearance of the lines, their marked lack of symmetry, and the character
of the violet component make this explanation doubtful. It seems more
probable that rising and falling masses of gas in the huge atmospheres of
these stars may be responsible for the observed displacements, and that the
partial analogy with the sharp absorption lines in the spectra of novae and
the displaced emission lines in the spectra of long-period variable stars may
be significant. The possibility of ionization effects in the atmospheres of
these stars should also be considered. No certain evidence of variation in
the structure, the intensities, or the displacements of these double lines in
the spectrum of a Orionis has been found during the period of more than a
year that the star has been under observation.

196 CARNEGIE INSTITUTION OF WASHINGTON

Microphotometer tracings of the spectra of some of these M-type stars
are being studied by Dr. Spitzer of Princeton University. The results should
be valuable because they are not confined to a single object but apparently
apply to the physical conditions in a whole class of important stars.

STELLAR SPECTROPHOTOMETRY

The measurement of line contours and intensities in high-dispersion spectra
of a selected group of stars has been continued by Dunham. A preliminary
study of contours, curves of growth, and ionization in these spectra, based
largely on the iron lines, is nearly ready for publication, and a more detailed
study of each spectrum is being undertaken with the assistance of Miss
Carlson.

The solar spectrophotometer is being rebuilt so as to permit a comparison
of different amplifiers. The arrangement is such that light from the same
part of the sun as that which is being analyzed is reduced in intensity, by
measured amounts, to equality with that in successive narrow sections of the
spectrum.

An experimental microphotometer, intended for the study of stellar spectra
and embodying many of the same optical and electrical principles, is also
under construction. Concave mirrors are to be used in order to eliminate
chromatic aberration and give resolution equal to that of the Schmidt cameras
used with the stellar spectrographs. Considerable time may be saved in the
reductions by recording the photographic densities directly by means of a
second concave mirror, which rotates on a transverse axis and scans a log-
arithmic calibration spectrum until the intensity in the latter equals that
at the point in the stellar spectrum which is being measured.

A series of radiometric observations of e Aurigse has been started by Pettit
at the coude focus of the 100-inch reflector to throw light on the question of
color excess. High sensitivity has been obtained with the aid of a thermo-
electric relay. The elimination of the accompanying disturbances required
much experimental work.

VARIABLE STARS

During the past few years about 130 additional Me and Se variables have
been observed by Merrill for radial velocity, making a total of about 280 now
observed ; but the program is still far from completion. Some progress has
been made in the study of typical variables near minimum phase, and ma-
terial for a general investigation of the bands in the yellow and red is being
gathered.

Joy has continued the spectrographic observation of irregular variables
without emission lines, of RV Tauri stars, and of short-period variables of
the RR Lyrse type. Of the latter group, W Canum Venaticorum has been
followed in detail, and a complete velocity-curve is now available. The
curve closely resembles the reflected light-curve. The range is 70 km/sec,
which points to the possibility of larger velocity ranges for these stars than
for the o Cephei stars. The spectral type varies from A6 to F6.

SU Ursse Ma j oris and X Leonis of the U Geminorum class were observed
at maximum light. The spectra are practically continuous.

MOUNT WILSON OBSERVATORY 197

A detailed investigation of the structure of the emission lines of o Ceti
has been continued, and several plates were taken at the last maximum with
the highest dispersion available at the coude spectrograph. The relative in-
tensity of the various components of the hydrogen lines was found to change
greatly with phase.

Investigation of the changes of line contour and intensity in spectra of the
short-period variable RR Lyrae considered in relation to phase has been con-
tinued by 0. C. Wilson.

Spectrograms of T Coronae (1866), Nova (CP) Lacertae, and Nova Aquilae
(1918) were obtained by Joy. The emission lines of hydrogen and helium
in T Coronae on June 6 and 7, 1938, were stronger relative to the continuous
spectrum than in 1921 and were single instead of double.

Observations of the spectra of faint old novae by Humason have been
continued and now include 16 objects which are classified as 0 Con when
the spectrum is continuous with no lines visible, and as 0 Em when emission
is present. In their present state these objects are decidedly blue, and the
extension of the continuous spectrum into the violet region corresponds to
that of 0- or possibly early B-type stars.

Densities of novae in the final state can be obtained by assuming that the
temperature is that of a normal O-type star. The densities of Nova Persei
(1901) and Nova Aquilae (1918), whose distances are reliably known, are
of the order of 220 and 70 times the density of the sun, respectively. For a
group of 14 other old novae whose distances are not so certain, a mean density
of the order of 60 times the sun has been found. Since the density of normal
O-type stars is of the order of 0.1 and that of white dwarfs 10,000 times the
solar density, the densities of old novae seem to be intermediate between
these two classes of stars.

INTERSTELLAR MATTER

From measurements of the faint and somewhat uncertain interstellar cal-
cium line X4226 in the spectrum of x2 Orionis, combined with a curve of growth
derived from interstellar sodium lines, Dunham has determined a value of
the ratio of the number of ionized to the number of neutral calcium atoms
in space. The result is approximately 2500 singly ionized calcium atoms
for each neutral atom. On the basis of this ratio and an estimate of the
intensity and spectral distribution of interstellar radiation, it appears that
approximately 20 electrons per cubic centimeter are required to maintain
the ionization of calcium at the observed level. Calculation then gives the
relative numbers of sodium, potassium, calcium, and titanium atoms in each
stage of ionization, and finally, the following highly tentative values for the
total concentrations in space (per cubic meter) : Electrons, 20,000,000.
Atoms: Na, 6; K, 0.2; Ca, 0.1; Ti, 0.001.

These values probably represent upper limits and are likely to be mate-
rially diminished when it becomes possible to take adequate account of the
reduction in the ionizing process which must result from the absorption of a
large fraction of the ultraviolet light emitted by distant stars.

The spectra of stars in which He does not greatly interfere with inter-
stellar calcium H have been observed by Sanford and O. C. Wilson as a

198

CARNEGIE INSTITUTION OF WASHINGTON

means of obtaining fairly dependable ratios of the total absorptions of K
and H. More than 130 plates were taken. This material permits satisfac-
tory evaluation of the total-absorption ratio except in the case of unusually
weak or strong interstellar lines, for which further observations are needed.

Merrill and Sanford have found that the ratio of intensity of D2 of sodium
to K of calcium, derived by direct comparison in spectra where both lines
were measured and also from the distance-intensity curves of the two lines,
is 1.6, with little evidence of any change in the ratio with intensity. This
value probably indicates about three times as many atoms of singly ionized
calcium as of neutral sodium.

High dispersion at the coude focus of the 100-inch telescope has been used
by Sanford for a detailed study of complex interstellar lines. In addition to
the stars in which such lines have previously been reported, those shown
in the accompanying table have been found to have double interstellar cal-

Ca II displacements

Total absorption

HD No.

Violet comp.

Red comp.

Violet comp.

Red comp.

829

km /sec
-42
+ 6
-59
-76
-80

km /sec
-13
+27
-12
-12
- 9

Angstroms

37022

93521

190429 N

0.07
0.10
0.07

0.11
0.41

190429 S

0.38

cium lines. The second and fourth were found by O. C. Wilson. The ve-
locities for HD 37022 (61 Orionis C) accord with the means (+1.1 and
+25.9 km/sec) of the Mount Wilson measures of the previously known
double interstellar lines in 5 Orion stars. The agreement and constancy of
the displacements for the N and S components of HD 190429, both of which
are spectroscopic binaries, is excellent proof of the interstellar nature of the
lines. Within the errors of measurement their total absorptions seem to be
the same.

The radial velocity of HD 8065, type cA2, was found to be large enough,
— 76 km/sec, to separate the stellar H and K lines clearly from the inter-
stellar lines, whose velocity is — 8 km/sec.

Two additional lines, M6203.0 and 6263.0, observed by Merrill and O. C.
Wilson should probably be added to the previously reported groups of un-
identified interstellar lines in the yellow and red. Moreover, it now appears
that the wide, diffuse feature at 314430, suspected for several years of being
detached, actually has an interstellar origin. Strong statistical evidence in
favor of this hypothesis was adduced by Beals and Blanchet at Victoria, and
confirmation is found in a recent investigation by Merrill and Humason
which shows the line to be stationary, within the errors of measurement, in
the spectroscopic binary HD 163181.

Recent trials by Merrill and William Miller show that interstellar D
lines are readily observable in spectra photographed with the 10-inch re-

MOUNT WILSON OBSERVATORY 199

fractor and the 15° objective prism. These lines offer the advantage that
the corresponding stellar lines interfere but little in types earlier than A3,
while with interstellar K interference becomes serious at B5. A preliminary
list of early-type stars examined on the objective-prism plates includes a
considerable number of the seventh and eighth apparent magnitudes whose
detached D lines are more intense than normal stellar D lines in type G.
Most of those of types B8 to A2 will probably prove to be c stars. When
the new photovisual refractor becomes available, this program will be com-
bined with one for the detection and reobservation of stars with bright Ha.

GALACTIC ROTATION

The normal radial velocities of the Cepheid variables have been used by
Joy to study the rotation of the galaxy. These stars are particularly suited
to the purpose on account of their distance, spectra, and concentration near
the plane of the galaxy. Photometric distances based on the period-lumi-
nosity relation were found to be largely affected by space absorption, for
which a correction of 0.85 magnitudes (photographic) per 1000 parsecs was
applied. The results indicate that the rotation plays an important part in
determining the apparent motions of these stars. Estimates of the galactic
constants, based on a high concentration of mass at the center, give: solar
orbital velocity, 296 km/sec; longitude of direction to center of rotation,
326?3; and radius of sun's orbit, 10,000 parsecs. The lack of observations
of southern stars which cannot be reached from Mount Wilson greatly
decreases the weight of the solutions.

A study of the motions of interstellar gas based on all available measure-
ments of detached lines was made by Merrill and Sanford. Curves for vari-
ous distances from 150 to 1200 parsecs approximate fairly closely to the
expected double sine curves characteristic of galactic rotation of the "plane-
tary" type. Altogether the data strongly support the conclusion of Plas-
kett and Pearce that interstellar matter takes part with the stars in galactic
rotation. A distortion in the curves for the nearer material in longitudes
125°-164° may perhaps have some connection with the stream motion of the
Taurus group. A least-squares solution yields for the constants of galactic
rotation

l0 = 329°, A = 14.8 km/sec per 1000 parsecs.

The nearer gases give a somewhat larger value of the constant A than those
at greater distances. Obscuration seems inadequate to account for this result,
which may possibly be due in part to a decrease in the average density of
interstellar gas beyond about 1000 parsecs from the sun.

MISCELLANEOUS

Observations of stars with peculiar spectra have been continued by Mer-
rill, and several spectra of classes R and N have been photographed by
Sanford with the coude plane-grating spectrograph.

The intensities of lines of ionized barium in early -type spectra have been
studied by Miss Burwell.

Considerable progress on the program of faint stars of large proper motion
and low luminosity has been made by Adams, Humason, and Joy. A list of

200 CARNEGIE INSTITUTION OF WASHINGTON

25 stars for which unpublished radial velocities were in excess of 75 km/sec
was prepared. Most of the highest velocities, eight of which are greater than
150 km/sec, are given by F-type stars with large proper motions.

Observations of stars in the Selected Areas have been continued by Strom-
berg. Thus far three or more spectrograms have been taken for 221 stars,
two for 48 stars, and one for 69 stars, leaving 92 stars of the list still
unobserved.

Several spectrograms of the white dwarf AC +70° 8247 were obtained by
Minkowski. Although the spectrum has been reported as continuous, micro-
photometer tracings of widened spectra show the presence of at least two
extremely wide, shallow absorption regions at about M.4135 and 4475. Unique
identification has not been successful ; a search for further absorption, espe-
cially in the red part of the spectrum, has therefore been started.

Among the faint stars observed by Humason were several in the region
of the Orion Nebula and an A-type star of seventeenth magnitude found by
Baade in the field of the old nova B Cassiopeiae. On the assumption that the
absolute magnitude of the A star is roughly +1.0, the distance modulus,
uncorrected for space absorption, is 16.0, which indicates a distance of
25,000 parsecs in a direction 125° from the galactic center.

In connection with their study of interstellar lines in spectra of early type,
Merrill and Sanford have revised the absolute magnitudes for the various
spectral subdivisions adopted on the basis of the distance-intensity relation-
ships previously used. The results show: (a) that differences in absolute
magnitude between stars with diffuse lines and those whose lines are better
defined are smaller than those originally found; (b) that there is a smaller
decrease from 09 to B8; (c) that c stars of classes B3 to B9 are fainter than
the assumed mean value —5.0, while those of classes A0 to A2 are brighter;
and (d) that the mean magnitude of a few Wolf-Rayet stars is — 2.9.

In spectrograms of 01 C and 02 Orionis and other stars embedded in the
Orion Nebula, taken with the 3-prism violet spectrograph, a sharp absorp-
tion line of considerable strength has been found by O. C. Wilson at X3888.
This line also appears on spectrograms of 01 C Orionis taken by Dunham
with the Schmidt-camera spectrograph at the coude focus. The line is
superposed on the broad diffuse H'C, absorption characteristic of the stars.
As there is no known interstellar line in this position, it may be attributed
to the transition 23S-33P° in the helium atoms of the nebula. The measures
obtained seem to indicate a systematic velocity of approach for X3888 as
compared with the emission-line velocities of the nebula. Presumably
this velocity difference is a result of the pressure of radiation from the stars
acting upon the helium atoms in the nebula. The intensities of the line in
the spectra of the various stars do not show a correlation with their red-
dening as measured by Baade and Minkowski. The line has been looked
for without success in stars associated with Messier 8 and 20 and in spectra
of the nuclei of two planetaries.

In a study by O. C. Wilson of the structure of H and K of calcium
in the spectra of late-type stars, a bright line was found within the wing
of H in the spectrum of a Bootis. Measures of position tentatively identify
the line as emission from hydrogen Hz.

MOUNT WILSON OBSERVATORY 201

GALACTIC NEBULA

RED PHOTOGRAPHY OF NEBULA AND CLUSTERS

Baade has continued his program of direct photography through red
niters, giving special attention to the region of the galactic center. The
investigation is of exceptional importance because it has partially pene-
trated the heavy obscuration that hides the nucleus of our system. A
survey in duplicate (red and blue) of the region galactic longitudes 300°
to 350°, latitudes +8° to —8°, made with the 18-inch Schmidt reflector
on Mount Palomar, fully confirms the strong selective absorption reported
a year ago. The greater space penetration of the red films, relative to the
blue, introduces marked differences in the pattern of obscuring clouds.
Further, various faint expended nebulosities, absent or inconspicuous in
the blue survey, are well recorded in the red, presumably by strong Ha
emission. For instance, NGC 6357, of which only one or two small wisps
appear in the blue, is an outstanding object on the red films, rivaling in
size the Orion Nebula and Messier 8. Among a number of new clusters
found during the survey, subsequent checks with the large reflectors dis-
closed half a dozen very heavily obscured globular clusters.

Other objects photographed in the red include the Crab Nebula, the
North America Nebula, various nebulosities in the Taurus obscuration,
a new emission nebula at R.A. 23h 49-8, Dec. +60° 8' (1937), and sev-
eral extragalactic nebula? and clusters.

One difficulty encountered in the work is the variable, and sometimes
heavy, sky fog appearing on the red films after only moderate exposures.
Since the fog on a given night is a function of zenith distance, its source
must be atmospheric — probably the red auroral lines. It seems possible
that the occasional difficulties encountered during the past half-year may
have been due largely to the high frequency of sunspots, now near maximum.
To test this point a spectroscopic investigation is now under way.

A REMARKABLE CHANGE IN THE VARIABLE NEBULA NGC 2261

On photographs taken by Baade at the end of December 1937, the pre-
ceding half of the variable nebula NGC 2261 appeared with its usual
intensity, while the following half was completely obscured. Since the
boundary of the illuminated area was a sharp, straight line, passing approxi-
mately through the exciting star, R Monocerotis, it seems evident that an
obstruction near the star threw a shadow on the following half of the
nebula. Poor weather permitted only a meager record of the phenomenon,
but a few photographs were obtained in January and February 1938. Dur-
ing this interval, the edge of the "shadow" moved from west to east at
the rate of 0'/08 per day, but lost its straight-line appearance and became
slightly ragged.

PLANETARY NEBULA

Duncan has continued his program of long exposures on planetary neb-
ulae, fifteen of which were studied. No new envelopes similar to those found
for the Ring Nebula in Lyra and NGC 6826 were discovered, but interest-
ing details not previously published were found in NGC 6210 and 6751
and in IC 3568 and 4634.

202 CARNEGIE INSTITUTION OF WASHINGTON

INTERFERENCE SPECTROGRAMS OF GALACTIC NEBULA

From interference spectrograms of the planetary nebula NGC 6826,
Minkowski has found a rather complicated distribution of radial velocities
such as might be expected from a rotation of the nebula around its minor
axis, with velocities decreasing from the equator toward the poles.

Minkowski has also obtained numerous interference spectrograms of Mes-
sier 8 and of the Orion Nebula, preparatory to a detailed study of the radial
velocities in these large diffuse nebulae.

EXTRAGALACTIC NEBULA

The major development during the past year has been the cooperative
study of two supernovae in extragalactic nebulae, in a manner more detailed
and comprehensive than has hitherto been possible. Supernovae represent
the sudden release of energy on a scale which far transcends that of any
other known phenomenon (one of the two recent supernovse reached a
maximum luminosity of the order of 109 suns). For the first time, suffi-
cient information has been assembled to investigate, rather than to speculate
upon, the behavior of matter and radiation under the extreme conditions
represented by the explosions.

In the general field of extragalactic research, emphasis has been shifted
from the study of the observable region as a sample of the universe, to the
detailed investigation of nebulae as stellar systems. The problems of nebular
structure and evolution have replaced, for the time being, the problem of

cosmology.

MOUNT WILSON COLLECTION OF PHOTOGRAPHS OF NEBULA

During the year an extensive observing program was finished by Hubble
which was undertaken for the purpose of obtaining good photographs with
the large reflectors of the 800 nebulae in the Shapley-Ames catalogue, north
of declination minus 30° and equal to or brighter than the limit of complete-
ness at photographic magnitude 12.9. The task of enlarging the Mount
Wilson collection of photographs to meet these specifications has required
the cooperation of several observers over a period of years. In the course
of this and other more special programs, photographs of many fainter
nebulae have also been assembled until the collection now includes about
2000 NGC objects and nearly 1000 given in the IC.

Since the material is complete for the brighter nebulae (over three-quarters
of the sky) and probably representative for the fainter objects, attention
has now been diverted from the compilation to the analysis of the data.
The investigations include detailed, quantitative studies of the sequence
of classification, of the relative frequencies of various types, and of the
small-scale distribution of nebulae.

SHORT-PERIOD CEPHEIDS IN MEMBERS OF THE LOCAL GROUP

Another cooperative observing program has been carried out by Hubble,
Baade, and Humason for the study of short-period Cepheids in the four
neighboring nebulae, M 31, M 33, NGC 6822, and IC 1613. Long exposures
with the 100-inch reflector were made for each nebula on 10 to 12 successive
nights. Some 60 new Cepheids have been identified. An investigation of

MOUNT WILSON OBSERVATORY 203

the variables in IC 1613 by Baade is practically complete. The magnitudes
are on the scale for very faint stars which he established in Selected Area
No. 68. This scale is now being transferred to the three additional nebulae.

SPECTROGRAPHS INVESTIGATIONS OF EXTRAGALACTIC NEBULA

Humason has determined apparent velocities and spectral types of 21
extragalactic nebulae. The list includes members of clusters and groups
of nebulae, and several large, resolved, and hence near-by nebulas, some of
which exhibit small negative velocities. He has also obtained a spectrogram
of the bright, central region of NGC 4111, with a dispersion about double
that previously used in the study of the rotation of this object. The new
spectrogram extends out 20" from the nucleus along the major axis. Since the
exposure time was not impracticably long, the larger dispersion will be used
for a more precise reinvestigation of the rotations of NGC 4111 and 3115.

SUPERNOVA

In the autumn of 1937 Dr. Fritz Zwicky, of the California Institute of
Technology, discovered two supernovae in the nebulae IC 4182 and NGC
1003. The observed maxima, apparent magnitudes 8.6 and 12.8, respectively,
were the brightest recorded since 1895 (Z Centauri), and the nebulae them-
selves were well placed for observation at the latitude of Mount Wilson.
The remarkable phenomena could therefore be studied in detail with the
large reflectors, and for the first time it was possible to use spectrographs
with adequate dispersions. The fortunate chance that two of these
mysterious objects could be studied simultaneously has added materially
to the significance of the results. The investigations at Mount Wilson were
carried on principally by JBaade (photometry), and by Minkowski and
Humason (spectrography), working in close cooperation with Zwicky, who
used the 18-inch Schmidt reflector on Mount Palomar.

Baade established sequences of photographic magnitudes and constructed
definitive light-curves covering the first observing season, and obtained the
data necessary to derive similar results based on red magnitudes. The
supernova in NGC 1003 was discovered before maximum and that in IC 4182
probably a few days after maximum. The two light-curves are similar and
follow the normal pattern. It is believed that it will be possible to observe
both stars for at least a portion of the next season.

The two nebulae are resolved, late-type spirals. From their brightest
stars, Baade has estimated distances of 0.9 X 106 and 1.5 X 106 parsecs
for IC 4182 and NGC 1003, respectively. Humason has found +475 km/sec
for the apparent radial velocity of NGC 1003, consistent with the estimated
distance, within the uncertainties introduced by accidental errors and
possible peculiar motion. The corresponding photographic absolute magni-
tudes of the supernovae are —16.6 and — 13.2, the former (for that in IC
4182) being the brightest that has been reliably determined.

SPECTRA OF SUPERNOVA

Minkowski, using dispersions of 75 and 150 A per mm at Hy, and Humason,
using a dispersion of about 400 A, have obtained (1) a series of 30 spectra
of the supernova in IC 4182, beginning August 29, 1937 (presumably about

204 CARNEGIE INSTITUTION OF WASHINGTON

nine days after maximum), and still in progress, and (2) a series of 10
spectra of the supernova in NGC 1003, beginning September 11, 1937
(about two days before maximum), and extending to January 6, 1938.
Minkowski is now analyzing this extensive collection of data.

Except for minor differences, the two series of spectrograms are closely
comparable at corresponding times after maxima and are consistent with
the fragmentary records of previous supernovse. The data indicate clearly
that the spectra of supernovse form a distinct class, entirely different from
the spectrum of any other known object (including ordinary novae).

The recorded spectra, which extend from X6800 to X3700, apparently
consist of wide, partially overlapping emission bands. The blue region
(X<5000) is dominated by a strong band in the neighborhood of X4600
but also contains several fainter bands. After some variations in relative
intensities during the first three weeks, a fairly stable pattern developed,
which persisted with only minor changes throughout the remaining period
of observation. However, the pattern as a whole shifted gradually toward
the red, the total displacement amounting to about 100 A by June 1938
for the supernova in IC 4182, and to about 70 A by January 1938 for that
in NGC 1003.

The behavior of bands in the red (/.>5000) was conspicuously different
from that of bands in the blue. The red bands varied rapidly, appearing
and disappearing in a manner somewhat resembling that of emission bands
in ordinary novse. Eventually, in February 1938 (after NGC 1003 was out
of reach), two narrow bands, each about 40 A wide, appeared at >.6359
and X6299 in the spectrum of the supernova in IC 4182. The stronger
band, at X6299, was still conspicuous in June 1938, when all the other bands
in the red had almost completely disappeared. Because of the rapid varia-
tions, the red shift easily observed in the blue could not be investigated
with confidence in the red region of the spectra.

Until the red shift can be interpreted, the identification of details in the
spectra presents a very difficult problem. At the moment, the only plausible
identification is that suggested by the close coincidence of the two narrow
red bands with the forbidden oxygen lines at X6364 and X6300. No features
have been observed which could possibly be attributed to hydrogen.

The narrowest details shown in the early spectrograms suggest widths
for individual bands of the order of 100 A. While it is not impossible that
individual bands may have had different widths, the data thus suggest
that, on the assumption of expanding shells, the velocities at most were
not greater than 3000 km/sec.

LABORATORY INVESTIGATIONS

SPECTRUM OF EUROPIUM

Data for the spectrum of europium, collected at intervals for some time
past, have been put in final form by King. These data include wave-
length measurements for approximately 3750 lines between X2100 and X10165,
nearly three times the number previously known ; the segregation of the lines
of neutral and singly ionized atoms by a comparison of arc and spark

MOUNT WILSON OBSERVATORY 205

spectra ; and the temperature classification of both neutral and ionized lines
by means of furnace spectrograms made at different temperatures. The
hyperfine structure of most of the europium lines and the great range in
their intensities caused unusual difficulty in obtaining both wave-length
measurements and intensity estimates. The number of plates required
to do justice to the various types of lines is much larger than for any rare
earth previously studied. The collection has been supplemented during the
year by spectrograms made with pure europium oxide contributed by Dr.
H. N. McCoy, which are free from the disturbing band structure present
on the earlier spectrograms. Absorption furnace spectra for the region of
shorter wave lengths, where the emission spectrum is weak, were used to
detect faint lines arising from low atomic levels.

Lines in the solar spectrum belonging to the rare earths are very faint.
With the exception of two neutral lines of ytterbium, those previously
identified are due to the ionized atom. A search for europium lines made
with the aid of the improved wave lengths and the temperature classification
revealed over twenty neutral lines, all very strong in laboratory spectra,
agreeing closely with faint, unidentified solar lines. As would be expected,
the lowest-temperature (ultimate) lines are found in sunspot spectra, while
those requiring higher laboratory temperatures appear in the solar disk.
In the Revised Rowland five solar lines were identified with singly ionized
europium. Use of the new laboratory data has increased this number to
twenty-seven.

SPECTRUM OF GADOLINIUM

King has begun an investigation of the spectrum of gadolinium with the
aid of a very pure preparation of the element supplied by Dr. McCoy.
About 60 photographs of furnace, arc, and spark spectra have been made,
and preliminary examination shows a very definite temperature grouping
of the lines. The lines easily measurable will greatly increase the number
now known.

For comparison with celestial spectra King has photographed the rich
band spectrum given by sodium vapor in the region X4500-A6700. These
bands appear in absorption on furnace spectrograms made at low tempera-
tures.

VACUUM SPARK

The large glass-plate condenser constructed in 1925 has now been replaced
by two commercial units, each of one-half microfarad capacity and 50,000
volts. These condensers perform fully as well as the large condenser,
and since they require only two square feet of floor space instead of the
forty or more occupied by the old unit, the change has been of great ad-
vantage in a laboratory as crowded as ours.

During the year Anderson has photographed the vacuum spark spectra
of a number of elements in the visual region M4500-7000. The exposures
required are enormously longer than in the region of shorter wave lengths.
Whereas 5 to 10 sparks suffice for most elements in the region M.2200-4500,
200 to 400 sparks are required to photograph the red part of the spectrum
satisfactorily. With these longer exposures the spark terminals not only

206 CARNEGIE INSTITUTION OF WASHINGTON

wear away considerably, but also are deformed into shapes very awkward
for the proper illumination of the spectrograph. By varying the initial
shape and size of the terminals it is possible to control the deformation to
some degree. Unfortunately, however, different elements behave differently,
so that thus far only a beginning has been made in overcoming the difficulty,
which, of course, must be overcome completely before this source can become
generally useful for laboratory purposes.

RULING MACHINES

About a year ago Babcock found that the screw of the new ruling machine
was undergoing spontaneous changes in form so large that it must be replaced.
After consultation with theoretical and practical experts on steel, followed
by exacting tests in our own shop, construction of a new screw was begun.
The cutting of the thread was completed in March and the various nuts
for lapping and using the screw are now being made.

The special shop formerly a part of the ruling-machine laboratory has
been restored and improved by the addition of valuable equipment no longer
needed at the Hale Solar Laboratory.

Several small gratings have been ruled on the old machine, chiefly to
study the distribution of brightness in their spectra. Both visual and
photoelectric methods of measurement have been used and their results
are in good agreement. It has long been known that the intrinsic brightness
of a given order of spectrum often depends on the angle of incidence.
Measurements show that in some cases the variation may be more than
twofold. It is not yet controllable at the time of ruling and calls for
further investigation.

With the aid of a photronic cell, Babcock has compared the luminous
efficiency of several of our gratings with that of excellent gratings ruled
elsewhere. The most interesting result appeared for two gratings, each
with high concentration in one second-order spectrum. The Mount Wilson
grating, although ruled on speculum and subsequently aluminized, is brighter
than the other, ruled on evaporated aluminium deposited on pyrex, in the
ratio 9:8. The comparison was for X5461 and was made with each grating
at its most favorable angle of incidence. Nevertheless, it seems probable
that evaporated aluminium ruled directly can be made to return more light
than aluminium superposed on a ruling already made. Under the most
favorable conditions gratings can now be ruled which return from 50 to
60 per cent of the incident, visible, monochromatic radiation in one order.
Various related details of technique are under investigation, several of which
now await trial rulings.

AUDITORIUM AND EXHIBIT HALL

The new auditorium and exhibit hall on Mount Wilson have continued
to serve their purpose admirably. The exhibit of astronomical photographs,
shown as transparencies, is open to the public on Friday evenings and for an
hour each afternoon. The dome of the 100-inch telescope is also opened each
afternoon and the mechanism and operation of the instrument are explained
to visitors. Friday evenings an illustrated lecture is given in the auditorium

MOUNT WILSON OBSERVATORY 207

preceding the demonstration at the 60-inch telescope, to which visitors are
admitted on these evenings. During the summer months, when the crowds
are large, visitors who cannot gain admission to the lecture hall go at once
to the 60-inch telescope. Hickox and Christie have given the evening
lectures and usually have served as curators in the exhibit hall when it
was open in the afternoon. During the year, 11,191 visitors were admitted
to the 60-inch telescope for the Friday evening demonstration — 1000 more
than for the preceding year, in spite of the fact that for three months Mount
Wilson was inaccessible to the public because of storm damage to the
Angeles Crest Highway.

CONSTRUCTION AND MAINTENANCE

60-FOOT TOWER TELESCOPE

After many years of constant use the 60-foot tower telescope is in process
of reconstruction. The remodeled instrument will include various features
of convenience suggested by past experience and many others made pos-
sible by modern developments in science and industry. To prevent the
shadow of the dome falling on the ccelostat at certain hours, the dome and
its supporting tower will be moved about four feet north relative to the
second tower, which carries the optical parts. The new ccelostat, provided
with a 22.5-inch mirror, will be controlled by a special synchronous motor
through a drive designed by Nichols, which will permit the observer to
change the rate without ascending the tower. An automatic guiding device,
operated by a photoelectric cell and a thyratron tube, will be a part of the
new drive. This device, recently developed by Whitford, is already in use,
and in practice has proved very effective. The second flat will be mounted
on a polar axis and otherwise will more nearly resemble that of the 150-foot
tower. The designs incorporate several other features of importance, and
later it is planned to include a new spectrohelioscope and a temperature-
controlled dark room. The shop work on the new instrument is well ad-
vanced and by the first of the year it should be possible to make the trans-
fer from the old instrument to the new.

ENGINEERING DESIGN

In the engineering department E. C. Nichols, assisted by H. S. Kinney,
has completed designs and drawings for the reconstruction of the 60-foot
tower telescope and for numerous special pieces of apparatus, among them
a spectrograph for use at the primary focus of the 100-inch telescope; a
21-foot Eagle-type concave-grating spectrograph for the Solar Laboratory;
new prisms and mountings for Cassegrain spectrographs IX and XI; a
6-inch camera and a truck for spectrograph XII; two microphotometers
and a microphotometer amplifier; a 9-inch ccelostat and second flat to be
used in forming a solar image at the exhibit hall; a spectroheliokinemato-
graph ; and a stereocomparator for the examination of plates up to 8 X 10
inches.

Preliminary studies and sketches have also been made for several projects,
including a remote control for rating the driving clock, and a declination
drive and lunar guider for the 100-inch telescope; a 10-inch photovisual
refracting telescope; and a 24-inch Schmidt telescope with mounting and

208 CARNEGIE INSTITUTION OF WASHINGTON

dome. A large amount of time has also been given to the preparation of
illustrative material for the Observatory publications and for the annual
exhibit of the Carnegie Institution.

INSTRUMENT AND OPTICAL SHOPS

Alden F. Ayers, for more than thirty years a most efficient foreman of
the machine and instrument shop, retired on August 1, 1937. To his deep
regret, serious illness during several months prevented him from rounding
out his full term of service. He has been succeeded by Albert Mclntire
as foreman. Owing to the reconstruction of the 60-foot tower telescope, the
shop activity during the year has been greater than usual. The new con-
struction includes all the apparatus listed in the preceding section and
many miscellaneous items such as work on the ruling machines, a mounting
for zero corrector No. 2 for the 100-inch telescope, the butane installation
for Mount Wilson, and much repair and maintenance work.

The optical work has been carried on by John S. Dalton with the assistance
of D. 0. Hendrix. Much work has been done on Schmidt cameras, includ-
ing three with focal ratios of 0.66, 1.0, and 1.0, and foci of 2, 3, and 9
inches, respectively. Other Schmidt mirrors of 17, 20, 26, and 30 inches
were also finished. A 36-inch grinding machine was built to care for this
work. A precision edger was also developed and built. The 7.5-inch, three-
lens zero corrector for the 100-inch telescope has been completed. Other
work includes the optical parts for two solar-spectrum photoelectric ampli-
fiers and for spectrograph 6B, two L2 prisms for spectrographs IX and XI,
guiding eyepieces, step wedges for photometry, and many small mirrors,
lenses, prisms, and filters.

BUILDINGS AND GROUNDS

The usual maintenance of the buildings in Pasadena and on Mount Wilson
has been carried on by A. N. Beebe, Superintendent of Construction, the
largest single item being the painting of the 150-foot tower telescope. The
paving of the road on the Observatory grounds begun last year to control
the dust has been extended around the 60-inch telescope and from there
halfway to the 100-inch dome. The result has been most satisfactory.
The damage to Observatory property by the severe rainstorm beginning
in the last days of February (see p. 184) was negligible. A butane heating
system has been installed in the kitchen range and in several of the rooms
of the Monastery.

Sidney Jones, Engineer, and Kenneth de Huff, Assistant Engineer, as
usual, have maintained the mechanical and electrical equipment of the
buildings and instruments on Mount Wilson.

THE LIBRARY

During the past year 393 volumes, 25 by gift, 43 by purchase, and 325
by binding, have been added to the library; the total number is now 13,743,
with over 10,000 pamphlets. The number of serial publications received
regularly in 1938 is 140; of these, 39 are gifts and exchanges, as are also
the publications, appearing at irregular intervals, of more than 200 observa-
tories and research institutions.

DIVISION OF PLANT BIOLOGY1

H. A. Spoehr, Chairman

In 1922 an extensive series of investigations was inaugurated, under the
support of the Carnegie Institution of Washington, to determine the manner
in which climatic influences are expressed in modification of plants, and the
manner in which they are differentiated to meet the complex demands of
various environments. These investigations, which have come to be known
as transplant or varied-environment experiments, have been carried out at
a number of stations ranging in altitude from sea level to the crest of the
Sierra Nevada. The extensive mass of observational and statistical data has
been collated during the past few years, and the results assembled for pub-
lication. The completion of this work marks a definite node in one of the
most extended investigations which have been carried out in the Division.

Two investigations dealing with the chemistry of the photosynthetic ap-
paratus of plants have been brought to publication. The first of these con-
cerns the leaf xanthophylls, a group of yellow pigments contained in all
chloroplasts. Because of the fact that these substances possess a very com-
plicated chemical structure and because the various members of the group
differ only very slightly in structure and in their chemical properties, their
isolation and purification have been associated with many difficulties. The
isolation of these extraordinarily sensitive compounds was made possible
largely through the development of special methods of chromatographic ad-
sorption. 3y this means and through the accurate determination of the ab-
sorption spectra reliable methods have been evolved for the characterization
of this important group of naturally occurring substances. The other in-
vestigation referred to concerns the mechanism by which the plant leaf ab-
sorbs the carbon dioxide of the atmosphere. This is the first step in the series
of chemical reactions comprising photosynthesis. The more exact deter-
mination of the chemical system which is involved in this first step has served
to establish another link in the series of chemical reactions comprising the
photosynthetic process.

Photosynthesis in plants is essentially an energy-storing chemical reaction.
This energy is obtained from the light which is absorbed by the pigments
in the leaves of the plant, and is used in reducing carbon dioxide to a carbo-
hydrate. The amount of energy which is required by the plant to carry
forward this chemical reaction is of fundamental importance in establishing
the chemical mechanism which is involved in the process. During the past
year a reinvestigation of the quantum efficiency of photosynthesis has been
begun by Drs. Robert Emerson and Charlton M. Lewis, with a view to mak-
ing certain essential amplifications of previous determinations with im-
proved apparatus, and with special consideration of the physiological charac-
teristics of the plant organisms used.

The recent publication of the results of thirty years' observation of changes
in vegetation on the fenced lands of the Desert Laboratory has attracted the
interest of both foreign and American workers who are dealing with the

xThe Central Laboratory of the Division is located at Stanford University, California.

209

210 CARNEGIE INSTITUTION OF WASHINGTON

problems of restoration and maintenance of grazing ranges. Shorter periods
of observation of the reproduction and growth of large desert perennials have
emphasized the slowness of growth of individual plants and the long periods
required to bring about change in the communities which they form.

The close of active field work on the Sonoran Desert project, which has
been one of the principal activities of the Desert Laboratory for the past
five years, has been followed by study of notes and collections preparatory
to publication. The work of the past year has been almost as fruitful as the
years of exploration, since it has given time for the study of living and
herbarium material and the collation of data on climate, vegetation, and the
distribution of some of the most highly specialized desert plants. The objec-
tive of these investigations has been the determination of the origin of desert
plants and their differentiation under the impact of the severe environmen-
tal conditions of the arid regions.

A publication of the Institution written by Ralph W. Chaney in collabora-
tion with Dr. Hsen Hsu Hu, Director of the Fan Memorial Institute of
Biology, describes a fossil flora from Shantung Province, China. This repre-
sents the first record in China of the Miocene vegetation so common in west-
ern North America. In spite of significant differences, the forests on opposite
sides of the Pacific contained many of the same trees. This supports the
suggestion that there was a migration route between North America and Asia
during the Miocene, probably across the Bering Sea region.

BIOCHEMICAL INVESTIGATIONS
H. A. Spoehr, J. H. C. Smith, H. H. Strain, and H. W. Milner

Leaf Pigments

Carotenes. Reexamination of the carotenes of carrot roots has demon-
strated the presence of relatively large quantities of a pigment having spectral
absorption properties similar to those of the flavoxanthins, a group of rare
xanthophylls. This pigment is readily isolated by adsorption upon magnesia
columns. It exhibits unusually strong absorption of light at short wave
lengths. Consequently, it may be detected in the presence of considerable
quantities of alpha- and beta-carotene by determination of the spectral
absorption properties of the mixture.

Leaves of several species of plants which are known to contain various
proportions of alpha- and beta-carotene (sunflower, tobacco, carrots, and
incense cedar) were found, by spectroscopic analysis of the pigments, to con-
tain little if any of the flavoxanthin-like carotene. Since carrot roots and
incense cedar are relatively very rich sources of alpha-carotene and only the
former contains much of the flavoxanthin-like pigment, it may be concluded
that the occurrence of the flavoxanthin-like pigment in natural products is
not directly related to the alpha-carotene content.

In order to confirm identification of the carotenes of butter reported from
this laboratory, comparative studies of the spectral absorption and chroma-
tographic adsorption methods have been made. Chromatographic adsorp-
tion has been found to be the most sensitive and specific method for the

DIVISION OF PLANT BIOLOGY 211

identification of alpha-carotene and the flavoxanthin-like carotene in mix-
tures of these with beta-carotene. Application of these methods to an investi-
gation of the carotenes of butter from Jersey cows has shown that the caro-
tenes of the butter are dependent upon the carotenes contained in the rations
of the animals. Addition of alpha-carotene and of the flavoxanthin-like
carotene to the rations of cows, which had previously received food con-
taining principally beta-carotene, resulted in the transference of all these
substances to the butter fat. These investigations, which were made possible
through the cooperation of Dr. H. R. Guilbert, of the University of California
at Davis, have demonstrated the wide applicability of the analytical methods
originally developed for the analysis of leaf pigments.

All green leaves examined thus far have been found to contain colorless,
fluorescent substances, which, from their behavior upon adsorption columns,
appear to be related to the carotenoids. Chemical investigation of these in-
teresting compounds has been hampered by the great difficulties encountered
in the isolation of the pure compounds. It has now been found that these
fluorescent materials occur in relatively very large amounts in carrot roots,
from which they are readily isolated by adsorption upon magnesia columns.
This discovery, by providing a supply of raw material, may make possible
a thorough chemical examination of these fluorescent components of leaves.

Some absorption spectra of leaf extracts and their significance. It has
previously been found that certain xanthophylls are readily destroyed by
oxidation when ordinary methods of extracting leaf pigments are used. This
led to some uncertainty as to the fate of chlorophyll under similar circum-
stances, because various methods of killing leaves may cause striking differ-
ences in appearance of the killed material. For example, with anaesthetics,
toluenized leaves dried in air lose their bright green color, and become
brownish, whereas when dried in hydrogen, they retain it. A sunflower leaf
when dipped in boiling water loses, inter alia, its intercellular gases and be-
comes more opaque, but is still deep green in color. Sorrel on the other hand
immediately turns brown.

The significance of such changes has now been studied by Dr. G. Mac-
kinney in two ways: first, by an examination of the absorption spectra of
suitably prepared extracts, and secondly, by application of the Tswett column
technique. The changes observed in the absorption spectra could be classified
into four groups:

1. Conversion of chlorophyll to pheophytin. This occurs most readily in
leaves of acid sap, such as sorrel.

2. Hydrolysis of the chlorophyll. Apparently of rare occurrence, it was
noted in certain sunflower extracts, and is presumably related to the alkalinity
of the sap. In this respect sunflower leaves would appear to be similar to
those of sugar beet, where it is known that the carbon dioxide exerts a marked
effect on the pH of the sap, which may become definitely alkaline.

3. Oxidation of the chlorophyll. This may be easily regulated in small-
scale operations, where 5 to 10 grams of leaf material are used. Where, how-
ever, a kilogram or more is taken, for the isolation of pure chlorophyll, it may
develop to serious proportions. If in fact there are but two chlorophyll com-
ponents, then it may be to oxidative changes that the supposed third com-

212 CARNEGIE INSTITUTION OF WASHINGTON

ponent owes its origin. There can be no chance of mistaking the other types
of change liable to occur where laboratory extraction procedure may be at
fault.

4. Changes in the ratio of chlorophylls a and b. Where methods appeared
satisfactory for a given species of plant, with no detectable degradation, it
became necessary to investigate the fixity of the ratio of the two known
components, which were separated on Tswett columns composed of inulin.
The problem was attacked indirectly, by showing that for seven species of
plants examined, there were only two components, blue and green, corre-
sponding to chlorophylls a and b, respectively. Preparations of the blue
component were found to be spectroscopically identical regardless of the
source, and the same was true for preparations of the green component.

Traces of degradation products may therefore yield erroneous results,
where dependence is placed exclusively on spectroscopic analysis. The
greatest danger arises with plants of acid sap. Anaesthetics, by modifying
phase relationships, exposing previously protected pigments to air, may have
an equally serious effect on plants whose sap is nearer neutrality. They
should therefore be used only in the presence of an inert gas. The ratio of
chlorophylls a to 6 apparently fluctuates within rather narrow limits regard-
less of age of tissue or time of day. These observations of course apply only
to healthy plants grown under field conditions. Substantial differences, how-
ever, are recorded for different species of plants. Adsorption studies with
inulin do not favor the hypothesis of a third component of chlorophyll. The
rapidity with which the individual components may be obtained, insuring
a minimum of change, has been of great value in evaluating the usefulness
of a method for a particular species of plant. Of the five general methods
employed, drying, direct solvent extraction, freezing, dipping in boiling water,
and anaesthetics, the first two are the most generally applicable. Drying
at room temperature in vacuo was particularly satisfactory for the acid
sorrel, but could not be applied readily to tobacco. It is obvious, when one
considers the diversity of leaf structures, that no one method can be in-
variably applicable, and it becomes important that a method should be criti-
cally examined for possible flaws when used on a particular plant.

Chloroplasts. The studies on silver nitrate reduction by chloroplasts, car-
ried out by Dr. Elliot Weier, have been brought to a conclusion and pub-
lished. They corroborated the suggestion of the French worker, Giroud, that
the ascorbic acid present in living leaves is responsible for the reaction. It
was demonstrated that chloroplasts in leaves killed by chloroform, toluene,
and formaldehyde fumes and by temperatures of — 50° C. to — 30° C. and by
100° C. in dry air lose their reducing powers. As indicated by the dichloro-
phenol-indophenol reagent, the ascorbic acid present in the living leaves was
destroyed when leaves were killed in this manner. If, however, leaves were
killed in a similar manner, except that an atmosphere of hydrogen replaced
that of ordinary air, the reduction of silver nitrate was still effected. The indo-
phenol test indicated that ascorbic acid was present in the extract obtained
from these leaves. When clover leaves were killed in boiling water the ascor-
bic acid was not destroyed and the chloroplasts were still able to reduce silver
nitrate. In some preliminary studies on pure ascorbic acid it was noted that

DIVISION OF PLANT BIOLOGY 213

the silver nitrate was reduced rapidly and energetically when the pH of the
ascorbic acid solution was 7 or higher, but very slowly when the pH was
4 or below.

Sorrel and Oxalis leaves, with a sap of pH 2 or lower, and clover leaves
which had been killed in 8 per cent acetic acid would not reduce silver nitrate
although ascorbic acid was present. Neither would the acid pulp of lemon
and pineapple reduce silver nitrate, although ascorbic acid was present. The
more alkaline rind of lemon strongly reduced silver nitrate and contained
ascorbic acid. In these cases ascorbic acid was present but, owing to the low
pH of the cell sap of sorrel and Oxalis leaves and the pulp of lemon and pine-
apple and of the acetic acid killing solution, silver nitrate reduction was not
brought about. The more alkaline condition of the lemon rind does not pre-
vent its reduction by the ascorbic acid present in this tissue. These ob-
servations indicate that ascorbic acid is responsible for the reduction of the
silver nitrate by the chloroplasts and suggests that it is confined to them.
This latter statement is, however, open to question, for it is possible that the
ascorbic acid is generally present throughout the cell and that special con-
ditions, such as increased alkalinity, within the chloroplast itself may account
for the more intense reaction in that body. Of particular interest is the
oxidation of the ascorbic acid which occurs immediately upon death of the
cell. This reaction does not take place in the living cell or, if it does, does so
at a very slow rate, even though the reacting substances are within proximity.

Carbon Dioxide Absorption by Unilluminated Leaves

In the process of photosynthesis as carried out by the higher plants, carbon
dioxide of the air is absorbed by the leaves and transformed into carbohydrate
under the influence of light. The leaf must possess a system for absorbing the
carbon dioxide prior to its transformation by light. Previous researches have
shown that the carbon dioxide of the air enters the leaf primarily through
the stomata. From the time the carbon dioxide passes through the stomata
until it appears in the form of carbohydrate virtually nothing has been known
of its activity.

The hypothesis has been proposed that chlorophyll reacts chemically with
carbon dioxide and the compound thus formed, under the influence of light,
is converted into carbohydrate. Because of the importance of this concept
to the formulation of a correct theory of photosynthesis, this aspect of the
problem has been given special consideration. It was found that, although
pure chlorophyll dissolves carbon dioxide, there was no evidence in these
investigations of chemical reaction between the two. Furthermore, leaves
containing large amounts of chlorophyll show no more affinity for carbon
dioxide than leaves completely lacking in this pigment, i.e., luteous, albino,
or etiolated leaves. The earlier experiments purporting to show interaction
between pigment and carbon dioxide can be explained by the physical solu-
bility of carbon dioxide in the pigment.

It has been assumed that the magnesium atom in the chlorophyll molecule
is the point of combination of the carbon dioxide with the chlorophyll. This
assumption appears to be doubtful, however, because removal of the mag-

214 CARNEGIE INSTITUTION OF WASHINGTON

nesium from the chlorophyll, to form pheophytin, increases rather than de-
creases the solubility of carbon dioxide in the pigment.

No evidence has been obtained from these experiments for the formation
of a compound between chlorophyll and carbon dioxide. Nevertheless, experi-
ments carried out several years ago demonstrated that even in the absence
of light, some leaves contain substances which absorb carbon dioxide. This
indicated that leaves possess a chemical system for obtaining carbon dioxide
from the air. Since sunflower leaves had been shown to have this system
highly developed, an intensive study of the carbon dioxide absorption process
in these leaves has been undertaken.

Initial observations showed that leaves killed by freezing absorbed more
carbon dioxide than living leaves. On the other hand, killed leaves contained
less carbon dioxide bound in chemical combination (e.g., carbonates and
bicarbonates) than living leaves. However, these two properties comple-
mented each other, so that when both living and killed leaves were saturated
with carbon dioxide, at one atmosphere of pressure, the amounts of carbon
dioxide bound by both were the same.

These facts indicated that the ability to bind carbon dioxide is not a func-
tion of the life processes of the leaf, but of some purely chemical system
contained therein. Analysis revealed that the carbon dioxide absorption
system was divided between the sap and solid material of the leaf.

The carbon dioxide fixed chemically by the sap appeared as bicarbonate
ion. The formation of the bicarbonate ion could be almost completely ac-
counted for by reaction of the carbon dioxide with the secondary phosphate
contained in the sap.

The carbon dioxide fixed chemically in the solid leaf residue could be
referred to the calcium and magnesium carbonates and phosphates present.
The material in the solid leaf residue responsible for combining carbon
dioxide, when isolated in analyzable form, was shown to have the following
composition:

CaO 51.45 per cent

MgO 1.29

MnO 0.65

P205 10.86

C02 33.39

Volatile not C02 3.47

Total 101.11 per cent

The presence of manganese in this material may be of special significance,
as it has been found to play a role along with the alkaline earths in the
absorption of carbon dioxide by water plants.

The reaction of carbon dioxide with the calcium and magnesium carbonates
present in the solid residue of sunflower leaves has interest in another direc-
tion. When stored in an atmosphere rich in carbon dioxide sunflower leaves
yield an expressed sap which is more alkaline than when they are stored in
air. It is possible that this observation may be explained in the following
way, however. Treatment of the leaves with carbon dioxide forms soluble

DIVISION OF PLANT BIOLOGY 215

bicarbonates from the insoluble calcium and magnesium carbonates present
in the leaf residue. The increased bicarbonate ion concentration represses
the ionization of the carbonic acid, thus reducing the acidity of the sap. A
further reduction of acidity occurs through the diffusion of carbon dioxide
from the sap into the air. By this loss of carbon dioxide the alkaline calcium
and magnesium carbonates are formed, which increase the alkalinity of the
sap still more.

The exact manner of participation of these various carbon dioxide ab-
sorbers in the photosynthetic apparatus is still obscure. It may be of im-
portance that they form a reservoir of carbon dioxide which may be drawn
upon by the leaf. The withdrawal of carbon dioxide from this reservoir is
made possible by the ready dissociation of the carbon dioxide from these
compounds by which it is first absorbed.

These experiments of the past year have established one possible link be-
tween the disappearance of carbon dioxide from the air through the stomata
of the leaf surface and its appearance as carbohydrate in the structure of
the leaf.

Amylolytic Activity of Leaves

The manner in which carbon dioxide influences the rate of starch dissolu-
tion in leaves has been investigated more intimately during the past year.
Concentrations of carbon dioxide which result in no visible injury to some
leaves, such as those of the sunflower, exert a pronounced inhibiting effect on
starch dissolution. This is not noticeable below concentrations of about 5
per cent. But with higher concentrations the carbon dioxide is increasingly
inhibitory.

That the rate of starch dissolution in leaves is considerably increased
through rapid loss of water from the leaves has been known for some time
from purely qualitative observations. Such observations are, however, sub-
ject to the uncertainties of the qualitative microchemical tests which have
been employed. This remarkable loss of starch with reduction of the water
content of leaves has now been substantiated on the basis of quantitative
starch determinations. Of particular interest in connection with the hydrol-
ysis of starch under these circumstances is the fact that it results in an
accumulation in the leaf of sucrose, while under ordinary circumstances mal-
tose and glucose appear, which are the normal products of hydrolysis of
starch. This rapid dissolution of starch under conditions of water deficit
in the leaf is also inhibited by carbon dioxide. That the rapid dissolution
of starch in leaves with relatively low water content is not due to higher
temperature of such leaves because of lower transpiration, has been shown
by the fact that even at 5° these leaves exhibit a remarkably high rate of
starch dissolution.

The effect of carbon dioxide on the rate of starch dissolution in leaves is
paralleled by the effect of this gas on the amylolytic activity. Below about
10 per cent of carbon dioxide in the air surrounding the leaf this gas appears
to exert a slight stimulatory effect. With higher concentrations of carbon
dioxide an increasing inhibitory effect has been observed. The carbon dioxide

216 CARNEGIE INSTITUTION OF WASHINGTON

also affects the pH of the leaf sap, in the sense that increased concentrations
result in an increase of the pH, i.e., in a reduction of the acidity of the sap.
Up to a concentration of about 15 per cent of carbon dioxide in air this effect
is hardly noticeable. These are the concentrations at which there appears
to be a slight stimulatory effect of the carbon dioxide on the amylolytic
activity. The influence of the pH on the amylolytic activity of leaves has
been reinvestigated, and maximum activity has been found to be at pH 6.3
to 6.6, although this is by no means universally true. The maximum varies
with the species and for some this has been found to be as low as 5. The
discrepancies in the results of various investigators may be due, in part at
least, to the fact that it is impossible to predict the pH of a reaction mixture
containing the leaf material from the pH of the particular buffer which is
used to control the hydrogen ion concentration of the mixture. The pH of
the reaction mixture must in each case be determined by means of a glass
electrode or by some other suitable means. The results of these investiga-
tions are now being published.

The Quantum Efficiency of Photosynthesis
Robert Emerson and Charlton M. Lewis

The reduction of carbon dioxide to carbohydrate requires a minimum of
112,000 calories per mole of carbon dioxide. In green plant photosynthesis,
the energy necessary for this process is obtained through the absorption of
visible light by chlorophyll. Photosynthesis proceeds normally in red light,
where the energy obtainable from a number of light quanta equal to the
number of molecules in a gram-mole (one mole-quantum) is only about
40,000 calories. Several light quanta must therefore be absorbed in order
to provide the minimum amount of energy required to reduce one molecule
of carbon dioxide. According to the present concepts of physics, absorbed
light quanta cannot act additively, but only individually, so we may suppose
that each absorbed quantum effective in photosynthesis brings about a single
elementary step in the process of carbon dioxide reduction. If three quanta
of red light were available for each molecule of carbon dioxide, there would
be 3 X 40,000 or 120,000 calories per mole, an amount greater by 8000 calories
than the theoretical minimum of 112,000. But each individual step must re-
quire some activation energy, for which a margin of only 8000 calories would
hardly be sufficient. Therefore it is generally believed that nothing less than
four quanta can be regarded as providing enough energy for the reduction
of one molecule of carbon dioxide to carbohydrate.

The minimum number actually required by the plant should give a clue
to the number of elementary photo-processes by which the reduction is ac-
complished. In 1923, Warburg and Negelein published the results of experi-
ments on the quantum efficiency of photosynthesis, indicating that under
ideal conditions, Chlorella cells could reduce one molecule of carbon dioxide
for each four quanta of visible light absorbed. This has led a number of
investigators to conclude that green-plant photosynthesis in general takes

DIVISION OF PLANT BIOLOGY 217

place by means of a reaction mechanism involving four elementary photo-
processes.

Although the quality and precision of Warburg and Negelein's measure-
ments have not been questioned, efforts to duplicate and extend their results
have been unsuccessful almost without exception, and consequently the value
of the original results in establishing the reaction mechanism of photo-
synthesis has been called in question. Warburg and Negelein found that
the maximum quantum efficiency was obtainable only with cells which had
been subjected to special previous treatment. They gave only scanty infor-
mation concerning the factors which produced cells capable of high quantum
yields, and none on how these factors influenced the internal characteristics
of the cells. They studied only a single species of organism, and it would
be desirable to extend their work to other species before drawing general con-
clusions concerning the mechanism of photosynthesis. The high quantum
yields were obtained only at light intensities so low that respiration exceeded
photosynthesis. Instead of assimilating carbon dioxide taken from the ex-
ternal medium, the cells were presumably using carbon dioxide produced
internally by respiration. But it is also possible that instead of carbon
dioxide, intermediate products of respiration were being reduced. Presum-
ably much less energy would be required for the conversion of such sub-
stances to carbohydrate than for the reduction of carbon dioxide to carbo-
hydrate. Finally, the results of Warburg and Negelein are indecisive on the
question of the activity of the yellow pigments. There remains a possibility
that they play a photochemical part in carbon dioxide assimilation.

In the fall of 1937, a new investigation of the quantum efficiency was begun.
The objectives were to specify more definitely the conditions under which
the high efficiencies reported by Warburg and Negelein were obtainable; to
establish relationships between physiological characteristics of cells and the
quantum yields of which they are capable; to extend the measurements to
light intensities where photosynthesis exceeds respiration, and to lower tem-
peratures, where respiration is minimal, in order to establish the quantum
yield for carbon dioxide taken up by the cell from the outside; to improve
both the intensity and the spectral purity in the red region, in the hope of
distinguishing between the activity of the two chlorophyll components; to
test the photosynthetic activity of pigments other than chlorophyll ; and to
extend our knowledge of quantum efficiency to other species besides Chlorella.

The first year has been devoted to the building of equipment and the
development of technique. To meet the requirements in red light, a reflecting
monochromator of large aperture and size will be built. A test model is now
nearing completion, and it is expected that this will be sufficiently powerful
to be available for quantum efficiency measurements, pending the comple-
tion of the final instrument. A number of modifications in the technique of
measuring photosynthesis are being tried out. Differences in the timing of
light exposures and dark periods lead to very different corrections for respira-
tion, which in turn give important differences in the computed quantum
yield, and a more thorough study appears necessary in order to establish a
technique as free as possible from uncertainties.

218 CARNEGIE INSTITUTION OF WASHINGTON

EXPERIMENTAL TAXONOMY

Jens Clausen, David D. Keck, and William M. Hiesey

This year the work has centered on bringing to publication the experi-
ments on the reactions of plants transferred to different climates as repre-
sented by the three transplant stations, Stanford University near sea level,
Mather at 1400 m. elevation in the Sierra Nevada, and Timberline at 3050 m.
The results have been accumulating since 1922, but the more comprehensive
data on which the statistical analysis is based have been assembled during
the years 1934 to 1937 after the inception of these experiments in their new
form. The data are so extensive that their complete analysis is still un-
finished, but the results of the investigations are clear from the studies already
made.

The most significant contributions are, first, the demonstration of the
delicacy of balance between the internal or gene-controlled factors and the
external environment; second, a comprehension of the orderly complexity
of species composition in relation to plant distribution ; and third, an evalua-
tion of the capacity of plants to adjust themselves to different environments.
The intricate reaction patterns of races of one species to different climates
indicate that the capacity for modification is important for the survival
and distribution of a given form. The visible effects of the interplay between
heredity and environment on plants are complex indeed, and the interpreta-
tion of the experimental results demands critical analysis.

Regional Differentiation into Ecotypes and Ecospecies

It is clear from the varied-environment or transplant experiments that
heredity governs the basic differences in appearance and the capacity for
survival in different habitats. Within one species, individuals of widely dif-
ferent hereditary composition may be found. Some species have developed
races or ecotypes, each obviously adjusted in its physiology to different en-
vironments, as, for example, to coastal, montane, or alpine conditions. Such
races can usually be distinguished by their morphology as well as by their
reactions to different environments. Within each ecotype, individual varia-
tions of genetic nature that are often associated with minor habitat differ-
ences usually further enrich the diversity within the species.

In the region of the Pacific slope, species of wide distribution are often
differentiated into four major races or ecotypes corresponding to different
climatic belts of this area. These include a Coast Range, a lower montane,
a subalpine, and an alpine ecotype. If the species grows along the immediate
coast an additional maritime ecotype may be found, and if it extends into
the Great Basin, it may there produce another ecotype. Evidently the con-
ditions in California are so varied that four to six major changes in heredi-
tary set-up are required if a species is to occupy the entire area from west
to east. When two ecotypes meet or overlap they may hybridize and produce
recombinations that survive, but as one leaves the zone of contact the parent
types on both sides can be recognized by their combinations of characters
and their ecological distribution. Frequently one or more ecotypes are re-

DIVISION OF PLANT BIOLOGY 219

placed by closely related species, called ecospecies, that may have originally
started as ecotypes.

The belts of vegetation formed by the various altitudinal ecotypes or eco-
species do not strictly follow horizontal lines but move up and down through
the canyons according to local conditions. Topographic irregularities with
their resulting climatic changes thus complicate the distribution of the races
or ecotypes of a species.

The Reaction Patterns of Ecotypes

When plants of a given species are taken out of their natural surroundings
and moved to a different climate, they change their appearance in a manner
and degree characteristic for each race or ecotype. Accordingly, at each of
the three transplant stations, Stanford, Mather, and Timberline, the same
collection of individuals, representing different ecotypes of one species,
presents to the observer a different aspect. Foothill, subalpine, and alpine
races of Potentilla glandulosa, for example, grow tallest at the mid-altitude
station and are most dwarfed at the alpine station, while the Coast Range
race is slightly more vigorous at Stanford, and, like the foothill race, perishes
at Timberline. The mid-altitude, subalpine, and alpine races of Potentilla
gracilis follow the same general trend in reaction as the corresponding eco-
types of P. glandulosa, but the closely related, exclusively alpine P. diversi-
folia is smaller at the mid-altitude station than at either Stanford or Timber-
line. Potentilla Drummondii has no Coast Range, foothill, or mid-montane
ecotypes, but its subalpine ecotype is tallest at Stanford, near sea level, and
shortest at Timberline. The alpine races of Achillea millefolium and Aster
occidentalis are tallest at the mid-altitude station at Mather, like the alpine
forms of Potentilla glandulosa, but, in contrast, become even more dwarfed
at the lowland station than at the alpine.

These and many other examples demonstrate that reactions to different
environments may change from ecotype to ecotype. The behavior of a given
race is, indeed, quite unpredictable, and this indicates that the relation be-
tween a plant and its environment is a very complex one. This fact is of
practical significance in the breeding of agricultural and forestry plants for
different climates.

Besides modifications in external structure which follow as a result of
changing the environment of a plant, observable adjustments in its seasonal
rhythm to fit the seasons of a new habitat take place. In their natural en-
vironment, the Coast Range ecotypes of many California species grow almost
continuously, developing vegetatively in winter and flowering early in spring.
Alpine ecotypes of the same species, on the other hand, remain dormant for
nine to ten months in their native habitat. When alpine races of some species
such as Potentilla glandulosa or Achillea millefolium are brought to Stan-
ford, the period of dormancy is reduced to two to three months, and others,
like Horkelia fusca, remain evergreen. Coastal ecotypes brought to climates
with the more severe winters of higher altitudes in the Sierras are forced into
winter dormancy despite their inherent tendency to continuous growth. From
this we conclude that races from different elevations change their growth
with the seasons of a new environment.

220 CARNEGIE INSTITUTION" OF WASHINGTON

Equilibrium with the Surroundings

Modifications in both external morphology and internal rhythm may be
advantageous to a plant in a different environment, but from the evidence
accumulated in the varied-environment experiments, these modifications do
not enable a plant to take care of itself very far outside its own zone.

For example, the Californian coastal ecotypes are in harmony with a
climate with mild winters and a long growth period. In contrast, at the
alpine station they are seldom or never able to mature seed, although they
reduce their size markedly and thus tend to hasten development. Moreover,
they seldom live through more than one or two winters. When they resume
spring growth in July after a long, severe winter, they appear starved and
are often unable to flower.

Alpine ecotypes are in harmony with a climate of long, cold winters and
short growing season. There they flower shortly after spring growth has
started and assimilate sufficiently to produce vigorous and floriferous plants
each spring. At the lowland station with its much milder winters their rela-
tive unfitness is manifested by reduced flowering and a weakened appearance
in spring following a period of dormancy substantially shorter than in their
native home. Many alpines do not even flower at Stanford.

The adaptive capacity of coastal and alpine ecotypes is therefore insuffi-
cient to allow either to live and to compete in the habitat of the other. It
is the difference in inheritance that enables them to succeed in their respec-
tive regions. From these and many similar observations it is evident that
the regional ecotypes are fitted to their climates. Their internal rhythm
is in equilibrium with the complex demands of their environment.

Chromosome Number and Environment

It has been suggested by several authors that a high chromosome number
is associated with fitness to extreme habitats, like alpine, arctic, and desert
conditions. Our findings are not in harmony with this theory as it was origi-
nally formulated.

Viola purpurea has only 6 pairs of chromosomes from 1000 to 3000 m. eleva-
tion in the Sierra Nevada, but 12 pairs in the Coast Ranges and in the Sierran
foothills. The yarrow, Achillea millefolium, has only 18 pairs of chromo-
somes in the Sierra Nevada up to 3300 m. elevation and in the arid Great
Basin, but has 27 along the Pacific Coast from California to Alaska. The
common mugwort, Artemisia vulgaris, in its widest sense, has 18 pairs in the
subalpine and in the alpine regions of the Sierras, in the Great Basin, and
in the Rocky Mountains, but has 27 pairs in the lower regions of the Sierras
and in the Coast Ranges north to the Aleutian Islands. A closely related
but distinguishable form with only 9 pairs occupies a narrow coastal strip
from northern California to British Columbia. In this latter instance the
lowest and the highest chromosome numbers are both found in the coastal
region. Zauschneria of the Onagracese has two coastal species with 15 pairs
of chromosomes, and one species with twice this number that has been able
to occupy not only the Coast Ranges but the mountains of southern California
and the Sierra Nevada as well.

DIVISION OF PLANT BIOLOGY 221

That a similar series of habitats may be occupied by one species without
change in chromosome number is illustrated by Potentilla glandulosa. All the
forms of this species have 7 pairs of chromosomes, but it has nevertheless
become differentiated into four regional ecotypes, occupying an altitudinal
range from near sea level to timberline.

From this and from evidence reported in the literature the conclusion
may be reached that, with but few exceptions, closely related species that
differ in chromosome number occupy different environments, but there is no
correlation between high chromosome number and extremity of environment.

Change of chromosome number is but one mode of regional differentiation.
The same end can be accomplished through development of a series of eco-
types without change in chromosome number. The primary difference be-
tween the two modes is that free interbreeding is prevented where chromo-
some numbers are changed, whereas no breeding barriers are created by
differentiation into ecotypes. Both modes are found in Achillea, for example,
where the 18-chromosome Sierran ecospecies has evolved a series of mark-
edly different ecotypes.

Experimental Results Expressed in Taxonomy

In analyzing the data from the varied-environment experiments, it was
found that the taxonomic status of almost all plant groups represented was
insufficiently known. The reactions of the living plants at the three stations
have given definite information on the number of ecotypes or ecospecies
involved and their taxonomic limits. It is not the appearance but the fitness
of plants to their environment which is the most important factor for sur-
vival. But since morphologic differences were often found to be correlated
with capacity for survival, they assume added significance where such cor-
relations can be experimentally demonstrated. In such instances it is possible
to map the distribution of ecotypes from herbarium material. The taxonomic
rank (ecotype or ecospecies) is being determined by the evidence of cytology,
and, as far as possible, from genetics. Step by step these integrated investi-
gations build up a picture of plant relationships useful in a critical and inter-
pretative taxonomy.

Selection Experiment

An experiment which is a logical sequel to the varied-environment studies
has been started this year at the Stanford, Mather, and Timberline trans-
plant stations. An F2 population of a cross made six years ago between the
Sierran foothill and the alpine ecotypes of Potentilla glandulosa has been
grown to maturity (see Year Book No. 36, 1937, p. 213), and each of the
six hundred plants was divided into three parts. One set of this triplicate
population was planted at each of the transplant stations this summer, and
individual records are being kept of each member.

It is the object of this study to determine which types survive in each of
the three sets of environments, and to observe their mode of reaction. It has
already been found that the foothill parent succeeds at Stanford and at
Mather but fails to survive at Timberline. The alpine parent, on the other
hand, thrives at all three stations, especially at Mather and Timberline. The

222 CARNEGIE INSTITUTION OF WASHINGTON

Fx hybrid survives at Timberline but not nearly as well as the alpine parent.
Because the F2 population represents an interchange of genes of two very
different climatic ecotypes, and includes segregants representing both parents
as well as a host of recombinations, this experiment should test the theory
of adaptive evolution by genetic recombination and selection.

Other Investigations

Continuing his exploratory investigations on transpiration of plants repre-
senting different altitudinal ecotypes of Potentilla gracilis, Mr. Hiesey has
found differences, the significance of which is the subject of further study.

Dr. Ake Gustafsson of the Genetics Institute of the University of Lund,
Sweden, investigated the cytology of the species of Horkelia, including those
used in the varied-environment experiments, while he was visiting the Central
Laboratory at Stanford. As far as his work has progressed, he has cytolog-
ical confirmation for the taxonomic conclusions reached by Dr. Keck, who,
in connection with the analysis of the varied-environment experiments, has
revised the genera Horkelia and Ivesia.

The preparation of a flora of the Harvey Monroe Hall Natural Area has
continued during the short stays of the staff members at the Timberline sta-
tion. The area includes about seven square miles varying in altitude between
3000 and 3800 m. The flora is rich for such a high elevation ; more than 280
species have already been found in the preliminary surveys, 155 of which
are of northern distribution, 31 extending to Alaska and 32 being circum-
polar. That many of these species are near the southern limits of their dis-
tribution is of particular interest.

INVESTIGATIONS ON THE CAMBIUM AND ITS DERIVATIVE

TISSUES

I. W. Bailey

Generalizations concerning the internal structure of the vascular plants
and its functional significance, when based as is commonly the case upon
an intensive study of a few selected species, should be checked by an exten-
sive investigation of a wide range of representatives of various families
and orders. We have shown, for example, that it is misleading and quite
fruitless to attempt to homologize all types even of commercial plant fibers
in a single structural model as various workers have attempted to do. A
study of the comparative anatomy of gymnosperms and angiosperms shows
that the walls of plant fibers are extremely complex and variable and exhibit
various fundamentally diverse structural patterns. Similarly, the physical
properties and the chemical composition of the plant cell wall fluctuate
greatly not only in different representatives of the gymnosperms and angio-
sperms, but also at times in different parts of the same plant.

In the case of the cambium and its derivative tissues, it is essential to
assemble authentic specimens from a wide range of gymnosperms and
angiosperms, from different phytogeographical regions, and from plants
of diverse form and habits of growth. Yale, Harvard, Oxford, and other
institutions are now cooperating in assembling such specimens. The inves-

DIVISION OF PLANT BIOLOGY 223

tigation of material of this character, although a task of considerable
magnitude, should ultimately provide not only a much clearer picture of
the salient lines of structural specialization and evolution in the higher
plants, but also an essential basis for testing various generalizations con-
cerning the functional activities of the cambium, xylem, and phloem. At
present, we are engaged in the study of (1) the tracheary cells of the
xylem, which are concerned in the upward movement of sap, and (2) the
parenchymatous elements of the xylem, which are considered to be physio-
logically significant primarily in the storage of elaborated material. In
addition, Dr. A. S. Crafts, Guggenheim Fellow, is making an extensive
investigation of the sieve tubes of the phloem, whose functional activities
are the subject of so much controversy among students of the downward
movement of elaborated materials. More extensive and reliable informa-
tion concerning the structure and the activities of specific cells and tissues
should eventually provide a clearer picture of the integrated activities of
the plant as a whole.

DESERT INVESTIGATIONS

Forrest Shrevb, T. D. Mallery, and W. V. Turnage

The Desert Laboratory is devoted to the study of a particular environ-
ment and its plant life. The work involves thorough investigation of the
environment as well as knowledge of the behavior of plants. The most
fruitful results are obtained when it becomes possible to establish a close
relation between environment and plant. In past years considerable work
has been done on the role which the broader climatic conditions play in
controlling the distribution of plants. In recent years increasing attention
has been given to the detailed differences of climatic and soil conditions
which often manifest themselves in a very small area. The smaller and
local features of climate are of importance in the distribution of plants,
especially in their selections of habitat, but have even greater importance
in controlling the life of the individual plant. The tendency of the work
at the laboratory has been away from the viewpoint of plant sociology
and toward the study of the life history and behavior of the individual
plant. The importance attached by many workers to the social features
of plant communities is largely subjective, and indeed somewhat homo-
centric. The relation of the desert plant to its physical environment is
very real and extremely important, and has a far more vital bearing on the
interpretation of the vegetation than do its relations to the biotic environment.

Substantial progress has been made during the past year in the study
of the life histories of plants as well as in the investigation of climatic and
microclimatic features of the desert environment. Some of the recent re-
sults of these investigations are already published or in press.

The Sonoran Desert Project

The five-year program of field work on the Sonoran Desert was concluded
at the end of 1937. Much of the past year has been spent in study of living
and herbarium material secured during the period of exploration of the

224 CARNEGIE INSTITUTION OF WASHINGTON

area, and in working over field notes and other data for publication. It
is planned to prepare companion volumes dealing respectively with the
flora and the vegetation of the Sonoran Desert.

Adequate treatment of the vegetation necessitates description of the
physical features of the area, including its geography, physiography, soils,
and climate. Maps are being prepared to show these features on the basis
of our own and previous work. This has been found to involve compilation
from various sources and much detailed work. Maps are also being pre-
pared to show the distribution of types of vegetation and important species
or genera. In addition to description of the various types of vegetation,
a group of about 100 plants of importance in the composition of the vegeta-
tion will be given individual treatment, covering their gross anatomy,
seasonal behavior, habitat preferences, and as much as can be learned about
their life histories.

One of the distinguished features of the Sonoran Desert is the relatively
large number of growth forms, or life forms, which are represented among
the dominant plants in its vegetation, doing much to give the physiognomy
of the desert landscape its striking character. A careful study of the life
forms has been made and a series of 25 is now recognized for this area,
constituting a rough physiological classification of the plants irrespective
of their phylogenetic relationship. If a classification of life forms is to have
more than mere utility in the description of vegetation, and is to be of service
in interpreting the relations between plant forms and environmental con-
ditions, it is necessary that it be based only on criteria of known physiological
significance. In contrast to the large number of life forms in the Sonoran
Desert it is to be noted that there are but few life forms among the domi-
nant plants of more favorable regions. The view has been developed that
the existence of highly competitive relations between plants in favorable
climates has resulted in standardizing the dominant types. In the far less
competitive conditions of the desert there has been an opportunity for the
independent development of very dissimilar types and also a favorable
condition for the long survival of the unstandardized types. The study of
the life forms, the known stages in their origin, their distribution, and their
relation to environment, bears promise of being significant in the interpreta-
tion of the history of the plant life of the region.

Work on the flora of the Sonoran Desert, which is in the hands of Dr. I.
L. Wiggins, of Stanford University, has been actively pursued during the
year. Dr. Wiggins spent the months from June to December 1937 at the
Royal Botanic Gardens, Kew, at the Gray Herbarium, Cambridge, and at
other taxonomic centers, studying the types of species described from older
collections in the Sonoran Desert. It was particularly important for him
to examine the types of the many plants of Baja California which were first
collected on the voyage of the Sulphur, in 1839, and those collected in Sonora
by Thomas Coulter in 1830. Keys which have been prepared by Dr. Wiggins
for a number of difficult genera have been placed in the hands of several
workers in order to test their soundness. Several taxonomists are generously
preparing treatments for Dr. Wiggins of families of plants in which they
have specialized.

DIVISION OF PLANT BIOLOGY 225

Mr. H. S. Gentry has spent part of the year at the Desert Laboratory
working on collections of plants made by him during the past four years
in the valley of the Rio Mayo in southern Sonora. He is preparing for pub-
lication an account of the vegetation of the lowland and mountain region
which he was the first botanist to explore, and an annotated list of about
1600 species of plants based on his collections. The lowland part of the
territory covered by Mr. Gentry is adjacent to the southern end of the
Sonoran Desert, which has made his observations and collections of great
value in connection with the work on that area. His knowledge of Sonora
and parts of Baja California has also enabled him to give substantial help
in the current work on the Sonoran Desert.

Field Investigations

Several brief trips have been made during the year into the lower eleva-
tions of the Sonoran Desert and into the Mojave Desert to make observa-
tions and comparisons of plant behavior at suitable seasons. In July 1937
a trip was made by Dr. Shreve, Dr. Mallery, and Dr. L. R. Dice, of the
University of Michigan, through the state of Chihuahua. The first purpose
of the trip was to find out the degree of similarity or difference between
the Sonoran and Chihuahuan Deserts, and the second purpose was to secure
a basis for considering the desirability of doing more work in the latter area.

South of the international boundary the Sonoran and Chihuahuan Deserts
are effectively separated by the forested Sierra Madre Occidental, but north
of the boundary the only barrier between them is a broad expanse of arid
grassland plains. Many plants characteristic of the northern ends of the
two deserts are also found in the arid grassland, but a larger number have
not crossed the barrier region. The Chihuahuan Desert is much poorer than
the Sonoran in its types of small desert trees. It is also poorer in the display
of succulent plants and lacks many of the life forms which are abundant in
the latter area. Although having a groundwork of similarity, the two deserts
show strong contrast in many features of the structure and habital distribu-
tion of their plant communities. A paper is in press which describes briefly
the vegetation of the part of the Chihuahuan Desert which lies in the state
of Chihuahua.

Environmental Conditions

Investigation of physical conditions during the year has been marked by
the discontinuance of certain observations that have yielded the desired
results, and by the extension of others in which greater detail or broader
basis of comparison is needed.

Rainfall records have been taken for periods of three to thirteen years
at lines of stations across the Sonoran Desert, at equal vertical intervals
across five mountain ranges, and at eight localities within a square mile of
the laboratory grounds. Taken in conjunction with the data of the United
States Weather Bureau and the Mexican Meteorological Service, the avail-
able figures have made possible an analysis of the rainfall conditions which
is now in preparation for publication. As a result of this work the line of
stations along the Camino Del Diablo and those on two of the more distant
mountain ranges have been discontinued.

226 CARNEGIE INSTITUTION OF WASHINGTON

In Arizona and northern Sonora in each of the two rainy seasons three
geographical regions are recognizable which differ in the relation of altitude
to rainfall. In winter the wettest section, relative to altitude, includes the
Sonoran Desert and the Mogollon Mesa, next is southeastern Arizona, and
the driest is northeastern Arizona. In summer the region which is wettest
in relation to altitude includes the desert, southeastern Arizona, and the
southwestern slopes of the Mogollon Mesa ; next are the northeastern slopes
of the Mogollon Mesa, and the driest section is northern Arizona. Abrupt
topography often serves to induce rain, and more so in winter than in sum-
mer. Illustrations include slopes immediately to leeward of high mountains
of small mass, narrow valleys and pockets surrounded mainly by higher
land masses, and also high mountain slopes.

Relative to elevation, rainfall in summer decreases on passing from south-
east to northwest. In winter the maximum is found in the lower Gila
Valley, with a decrease on passing northwestward. Near Tucson, on an
area of one square mile the irregularities of summer rainstorms are smoothed
during a season. The smoothing of the winter rainfall is not so great and
it is therefore more variable over a small area than the summer rain. Over
larger areas the rainfall of a given summer is more unequally distributed
than that of winter. The departures from normal of a season of rain from
place to place over the region considered are irregular, only very dry or
very wet years showing high uniformity. When the individual departures
are summed and divided by the number of stations, in order to obtain a
composite picture of the regional variation from year to year, the winter
rain is found to vary from the normal more strikingly than does the summer
rain.

Routine readings of soil moisture and runoff have been continued on the
revised plan adopted early in 1937. These observations are making it clear
that the moisture content of the soil below 2 to 3 feet over the general
surface of the desert is very rarely built up by even the heaviest rains. The
percentage of runoff in summer ranges from 40 to 62 per cent of the rainfall
yield, and in winter from 5 to 29 per cent. During the past four years the
total runoff has been 38 per cent of the total rainfall. Schwalen has shown
that the stream flow of the Santa Cruz River and its principal tributary,
the Rillito, draining over 3000 square miles of desert and desert grassland,
is "less than 2 per cent of the total precipitation." These figures indicate
that about 36 per cent of the precipitation penetrates the soil between the
place at which it falls and the minor drainageways or else in the sandy
beds of the small tributaries of the principal rivers. It also indicates that
little more than 2 per cent of the rainfall finds its way into situations
where it is likely to contribute to the ground water of the central flood
plain of the Santa Cruz Valley. These considerations are illuminating with
reference to the water supply for perennial plants of flood plains and the
margins of streamways. They have little application, however, to the con-
ditions for plants of rocky slopes and hills, where many practical difficulties
have deterred investigation.

The investigation of soil temperature has necessitated selection of in-
strumental equipment suited to the very dissimilar conditions of the surface,

DIVISION OF PLANT BIOLOGY 227

where high daily ranges prevail, of levels from the surface to 3 feet, where
a smaller daily range occurs, and of levels below 3 feet, in which there is
no daily range and only a small annual one. A Foxboro thermograph was
installed in 1937, suited to record the high range of a shallow level. Friez
soil thermographs have been in operation at 3 inches, 1 foot, and 2 feet,
and weekly thermocouple readings have been taken at 3, 6, and 12 feet.
All these instruments are in the clay soil of the Santa Cruz flood plain.
Accuracy, simplicity, and moderate cost of the instrument employed have
been best attained for depths below 3 feet by use of thermocouples and
portable galvanometer. Insulated thermocouple wires in the soil at depths
of 3, 6, and 12 feet have not changed their constants during a year of use,
and furthermore can be calibrated in place at any time. The importance
of careful instrumental exposure is shown by comparison of records taken
for 12 months at 6 feet by thermocouple and by a mercurial thermometer
placed in a metal tube running horizontally into the soil from the insulated
cellar of the percolimeter. The latter instrument has shown an annual
range 35 per cent greater than the thermocouple.

Behavior of Desert Plants

In the course of field work in the Sonoran Desert a large collection of
seeds was made, representing many of the common perennials of the lower
altitudes and southern part of the area. The germination requirements,
characteristics of the seedling, and early growth are totally unknown for
most of these plants. During the spring of 1938 a systematic study of this
material was begun. Up to the present time 90 species have been subjected
to culture and observation under uncontrolled greenhouse conditions without
special seed treatment other than dusting. Of the species planted about 45
per cent gave no response and will require various treatments to break their
dormancy and stimulate germination. A temperature of 80° F. or higher is
required to start germination in most of the species studied. Best growth
is obtained when the minimum temperature does not fall below 50° F.

The seedling stage of some of the most highly specialized desert perennials
shows very little resemblance to the adult plants as found in nature. This
is strikingly exemplified by Holacantha Emory i and Canotia Holacantha,
leafless green-stemmed trees which bear numerous well-formed leaves in the
seedling stage. A number of other highly modified forms give evidence of
their phylogenetic relationship in their juvenile foliage but do not suggest
it in the mature leaves. In the small tree Acacia Willardiana the pinnate
leaves characteristic of the genus are found in the seedling, while the leaf
functions are carried on in the mature tree by broadened petioles which are
simple and entire in form. This transformation is common among the acacias
of South Africa but no other case is known in the desert of North America.

A number of small trees develop an enlargement of the stem very early
in the course of seedling development, including Ipomcea arborescens, Ery-
thrina flabelliformis, Bursera spp., Fouquieria peninsularis, and Idria col-
umnaris. The enlarged portion may extend from below the soil level and
taper sharply toward the top or it may develop in the region of the seed

228 CARNEGIE INSTITUTION OF WASHINGTON

leaves, tapering toward both the top and root, imparting a spindle shape to
the young plant.

Plants raised from seed which have become well established in the green-
house are then transplanted to the garden or other favorable places on the
grounds. The number of species under observation which were raised from
seed in previous years or collected as living material is about 240.
This material is helpful for the identification of plants found at seasons
when they were not in flower or fruit, and gives opportunity to observe the
development and growth of many species found in the distant parts of the
Sonoran Desert. In a few cases unknown plants have been raised from seed,
brought to maturity, and identified, among them the large-fruited asclepia-
daceous vine Mellichampia ligulata. A number of plants have been raised in
sufficient quantity to furnish material for anatomical study. The structure
of stem and root is almost completely unknown in this group of plants, and
the derivation of tissues and the relative proportion of medulla or cortex
involved in the striking specializations require investigation.

No broad generalizations can yet be made from the study of the early
life histories of the plants now under observation. At present the results
consist essentially in a record of details with reference to each plant. It is
already evident, however, that the diversity which is manifested in the life
forms of the Sonoran Desert is also found to extend to their seeds, modes of
dissemination, germination, and early development.

For a number of years the growth and reproduction of the creosote bush,
Larrea tridentata, has attracted investigation. In the characteristic evenly
spaced stands of this shrub the majority of the individuals appear to be old
and slow of growth, and natural reproduction to be very poor. It has fre-
quently been noted that removal of the shrubs or disturbance of the surface
is followed by the appearance of many young plants. In 1928 a series of
eight areas 15 m. square was laid out and subjected to different treatment
(as reported in Year Book No. 29, 1930, p. 225). After the summer rains of
1929 it was found that reproduction had been most active on the area in
which the surface soil had been turned over to a depth of 10 cm., and much
less active on areas which had been vigorously raked or covered with new
soil. The number of seedlings that appeared in these areas was respectively
136, 14, and 10. No reproduction took place on the control areas and the
influence of the removal of old bushes was slight. In 1938 the number of
seedlings surviving on the above three areas was respectively 42, 9, and 10,
and 3 additional ones had appeared on the control areas. Most of the
1929 seedlings now vary from 5 to 15 cm. in height, but a single one has
reached 137 cm. The widely scattered crop of induced seedlings was reduced
to 37 per cent of its original number in 10 years. The appearance of 3
new plants on the 1800 sq. m. in 10 years probably indicates the normal
rate of reproduction under undisturbed conditions.

In 1930 a small area on the grounds of the laboratory was noticed to have
a very heavy stand of young creosote bushes, apparently induced by the
shallow excavation of an Indian village site ten or fifteen years before. An
area 9 X 15 m. in size was mapped and the maximum height of each of the 226
plants was recorded on the map. This area was remapped in 1938. Ten new

DIVISION OF PLANT BIOLOGY 229

plants had appeared and 15 of the original ones had gone. The growth was
plotted, showing a mean height increase of about 50 per cent, 61 individuals
having made this or a greater growth. There were 51 plants which were not
as high as in 1930, having been eaten back repeatedly by rabbits. Plants
which were less than 50 cm. high in 1930 suffered more from rodents than
taller ones. Later observation of this area will show whether it thins out
to a stand of normal density as the plants become older and larger, and the
results will have an important bearing on the question of competition or
independence in desert plants. The elimination of only 5 individuals in a
population of 226 over an eight-year period gives some indication that the
selective processes of competition for light and soil moisture are not strong,
and are indeed subordinate to the deterrent influence of rodents.

In June 1926 Godfrey Sykes began measurements of height growth of the
sahuaro (Carnegiea gigantea) at a place on the grounds where they exhibit
their maximum abundance. His method of measurement involves a cement
datum point and avoids the thickly clustered spines at the apex. Readings
have been continued for twelve years on his series of 9 plants of various
heights. For three years the measurements were taken monthly. Height
growth varies from 3 to 4 inches per year except in the plants less than 12
inches in height, which grow much more slowly. The monthly readings
show that growth takes place only during the summer rainy period, whereas
during the dry spring months there is often a slight shrinkage.

The mesquite tree {Prosopis velutina) reaches its greatest size and abun-
dance on deep flood-plain soils. Leaves appear and shoots begin to elongate
in March or early April, at the time of greatest atmospheric aridity, but in-
crease in trunk diameter is confined to the summer rainy season. The per-
formance of the mesquite has been followed for the past eighteen months
and changes of stem diameter measured by the dendrometer. Concurrent
records of rainfall, infiltration, soil moisture, and soil temperature close to
the measured trees make it possible to evaluate the principal variables which
affect growth. Trunk swelling is minute after rains of less than 0.25 inch,
and appreciable shrinkage has followed light rains in the dry season. Swell-
ing follows all heavier rains throughout the year, but in winter is soon fol-
lowed by compensating shrinkage. Growth of leaves and shoots is made
when the surface soil is dry, but the greatest increases of trunk diameter
follow the wetting of the surface soil by heavy rains in midsummer. In
twelve months the net increase in diameter of a stem of 10 cm. was 0.8 mm.
The water table beneath the measured trees is about 45 feet below the sur-
face. If the roots reach that depth they do not secure enough water to cause
trunk growth.

ECOLOGY

Factor and Function in Adaptation

F. E. Clements, F. L. Long, and E. V. Martin

In the early investigations of adaptation by means of the transplant
method, it was found that the various environments operated not so much
as a complex but rather in terms of a major factor modified in turn by several
other factors. Change of altitude in itself did not modify growth rate and

230 CARNEGIE INSTITUTION OF WASHINGTON

stature, but only in those cases where the water relations were significantly
different. Alpine dwarfs native at 12,000-14,000 feet on Pikes Peak re-
mained dwarfs in dry situations, whether at the Alpine Laboratory at 8000
feet, the Plains Garden at 6000 feet, or near the sea level at Santa Barbara.
Likewise, the transfer of tall plants from low to high elevations produced
dwarfing in the dry climax areas, but not where moisture was more abundant.
Even in the relatively moist spruce forest, alpine species usually remain
diminutive, except when the water content of the soil is fairly high.

The explanation of this general behavior has been found in a series of con-
trol experiments with graduated amounts of water and of light. In all of
these, stature increased with the percentage of water available, while in the
case of light the maximum height occurred at 25 per cent of sunlight and
fell off both toward sunshine and toward the lowest intensity of 6 per cent.
This is apparently to be explained by the correlation between the tension due
to turgor and the amount of growth materials supplied by photosynthesis.
With respect to mineral nutrients, the results were somewhat similar; branch-
ing was greatest and dry weight highest with the largest dosage of fertilizer,
but plants in the intermediate condition were tallest. Temperature has been
found to promote woodiness and to increase the life span, but as a rule its
specific effects are less definite than with the other three factors, while
humidity and wind are chiefly concerned in water relations.

As a consequence of the combined study of factors and functions, the
experimental system has steadily assumed more definite form, and the ad-
justment between nature and control is expressed in four successive stages,
namely: (1) native habitats; (2) slight control, chiefly watering during
drought periods; (3) moderate control by means of dry and wet gardens,
shade tents, lath houses, etc.; (4) practically complete control of water,
light, nutrients, soil, length of day, and so forth. In all of these, a single
factor, water, light, or nutrients, has been the chief agent of modification
and the others have been equalized in whole or in part. Through many repli-
cations by species and seasons, this study has led to more or less definite
correlations between factor, growth, and form, reinforced by the measure-
ment of functional response in phytometers. However, it is essential to link
together factor and form in a large number of transplant species by means
of functional determinations, and this task is now well begun.

Of the three major factors, water has been found to be the most important
qualitatively, followed somewhat closely by light, while nutrients are mostly
quantitative in effect. Transpiration is measured with much accuracy under
field and garden conditions by weighing sealed or free phytometers. The
primary difficulty is found in transferring native and experimental plants to
containers safely and in growing them from seedlings in phytometer cans.
Hence, in the more difficult cases, recourse is had to short-period potometers
of shoot and leaf, weighing detached leaves, cobalt paper, etc. These yield
approximate values, which can be improved by projecting them against the
readings from standard phytometers. In the case of photosynthesis, the
method of gas analysis is hardly practicable in the field, and the determina-
tion of photosynthate and dry weight yields the best correlation with the
various light intensities.

DIVISION OF PLANT BIOLOGY 231

Such direct factors operate immediately upon the vegetative body and
their effect upon the reproductive organs is exerted for the most part through
the food stream. Marked or extreme dosages are usually reflected in the
size, number, or arrangement of flowers, but deep-seated changes in flower
or fruit are more readily induced by the manipulation of the food current
itself. This is accomplished in a variety of ways, by severe pruning, by
excision, by compressing, by injecting glucose, vitamins, poisons, etc., with
the result that nearly all species thus treated have shown fundamental
alterations in number plan, the regeneration of staminodes and pistillodes,
or the reduction or abortion of stamens, pistils, or perianth. The speciali-
zation that has produced the social flowers of grasses and composites has
provided the most fertile field for both direct and indirect modification.
This is not merely because of the longer line of evolutionary steps to be re-
traced, but especially because the spikelet and head are relatively recent
structures, into which vegetative parts such as bracts and scales have been
built. Consequently, the glumes and lemmas of grasses and the involucral
bracts and chaff of composites respond to water and light much as do their
prototypes, the leaves of a shoot.

Although instrumental and phytometer records have been made annually
at the Alpine Laboratory for two decades, the study of the process by which
functions call forth adaptation has demanded a more complete installation
specially fitted to the comprehensive series of fourteen climatic and edaphic
gardens. This has been carried out during the past two seasons and con-
tinued in part during the current year. For the three climatic gardens, the
relative transpiration on the basis of leaf area was 10 at the plains, 6 at the
montane, and 4 at the alpine station. At all the gardens transpiration in the
lath houses with 25 per cent light intensity was approximately one-half that
in the sun. There was a marked difference between the dry weights in the
sun and in the lath houses at the climatic stations, namely, 100 times greater
at the plains, 10 times in the montane, and 4 times at the alpine, the striking
reduction with altitude being a response to decreasing temperature. With
respect to nutrients, the native gravel soils gave dry weights of 20, 10, and 1
respectively from plains to montane and alpine, while in an imported sandy
loam the figures were 100, 33, and 1. This decrease with elevation is partly
a matter of water, but largely one of temperature, the seasonal average be-
ing 7° C. less at the montane and 20° C. less at the alpine than at the plains.

The five-year intensive study of factors and functions on wandering and
stable dunes along the seacoast at Santa Barbara has been concluded and it
is expected that the results will be published during the year. The dune
project as a whole not only possesses high intrinsic value as the investigation
of a distinctive habitat and its succession, but gains further interest because
of certain similarities with alpine situations. The general assumption that
the dwarf and procumbent forms of dunes are a response to aerial factors
has not been supported by the results, which indicate that soil factors, both
water and nutrients, are the primary control. However, the fact that species
grown in the series of three different soils in the main garden and on stable
and wandering dunes show the highest osmotic concentrations in the latter
indicates that air factors are not negligible. Survival is much the lowest in

232 CARNEGIE INSTITUTION OF WASHINGTON

the shifting sand, and only a few species, mostly shrubs, are able to pass
successfully through the long dry season. Annuals show a much lower mor-
tality in stable sand, while perennials that persist through the first year
usually become permanently established. In some cases at least, this is due
to the ability of the roots to follow the retreating water table of the rainy
season downward from the 1-foot to the 6-foot permanent level. The general
conditions are favorable to the accumulation of woody tissue and a number
of annuals have developed into evergreen half-shrubs. This is in accordance
with the high survival noted for transplanted shrubs.

With the object of throwing further light upon the fixity of stature and
other characters in alpine dwarfs and lowland "tails," reciprocal transplants
have been made of a selected group of species each season for a period of
three years. During the present season, the transfer of the alpine species
was made as soon as they appeared above ground, with the purpose of deter-
mining what changes take place during the first summer. Owing to the much
later renewal of growth in the alpine zone, lowland plants could not be
removed immediately upon emergence, but this was done while they were
still short. Care was taken to reduce the shock of transplanting to the mini-
mum and the response of the plants in continuing growth indicated that this
had been accomplished. At the same time, the alpine species were also
transplanted through a transect of five habitats in the alpine climate, but
with varying water contents. Final results will not be available until the
end of the growing season, but the initial response of many species indicates
that adaptation to the new situation may occur more or less completely dur-
ing the first year.

Timely rains in the Pikes Peak region have brought forth a larger number
of modifications than has been the case in the several dry years that preceded.
The majority of the morphological conversions have concerned grasses.
Sporobolus airoides has been changed into S. Wrightii after two years of ex-
cess rainfall in the dunes, and the European Agropyrum caninum into A.
subsecundum by transfer to half-shade. Trisetum montanum has been con-
verted to spicatum in the sun ; Elymus ambiguus with 2 spikelets into con-
densatus with 3-4 at a joint under optimum conditions of water and nutrients ;
and Bouteloua curtipendula into uniflora as a consequence of renewed bloom-
ing in midwinter. Special attention has been paid to methods of modifying
the major criteria employed to separate species; thus, the triangular calyx
lobes of Amorpha fruticosa have been changed to the acuminate ones of A.
calif ornica by heavy watering. This has also called out dwarf racemes with
minute flowers two to three months before the leaves instead of with them
and has produced decumbent rooting stems. Cushion plants typical of the
alpine tundra have developed stems and peduncles many times longer than
normal, and in some the trailing stems root at the joints. This feature has
been called forth in a number of forbs by reduced light or increased water,
and the decumbent habit has been induced in a number of perennial grasses.
As usual, extreme conditions or manipulation have led to striking changes,
as in the number plan of Ruta, the ratio of staminate to perfect flowers in
Scandix, and the production of regular flowers with the conversion of stami-
node to stamen in Scophularia.

DIVISION OF PLANT BIOLOGY 233

The greater number of the species and many of the genera made use of
in the transplant and other experiments in adaptation and origin have not
been examined for chromosome numbers. A comprehensive program in this
field has been initiated and it is hoped not only to ascertain the numbers
for many of the species concerned but also to discover whether the various
methods of manipulation produce any changes in number of chromosomes.

Climax, Succession, and Conservation
F. E. Clements and E. S. Clements

The climatic cycle of the past ten years has recapitulated in miniature
the much larger cycles of postglacial times and the more remote geological
past. This is particularly true of the protracted drought phase with its
marked effect upon vegetation and soil, and the human responses that depend
upon them. The period has not been sufficiently long for vegetation to
exhibit migration on the same large scale as in the past, but local migration,
destruction of species populations, changes of composition, and modification
of form have all occurred in prairie and plains since the advent of dry years.
These have furnished support in dynamic terms to the basic ecological thesis
that the major communities of the globe and their constituent species are
responses to the great climates and that they migrate and evolve as the
climates shift during long periods. In other words, each climax, as well as
its more recent subdivisions, springs from an earlier vegetation through
the further evolution of its dominant species under climatic stress. Hence,
the endeavor to reconstruct the phylogeny of climaxes and the climatic
pattern of geological periods necessitates retracing the migration and evolu-
tion of the species of trees, grasses, and herbs that give each its character.
Such results are flowing in increasing measure from the experimental studies
carried on in the transplant gardens, and these serve an additional purpose
in disclosing the complex nature of vegetation and the processes that occur
in it. Out of these investigations has come the ecological basis for utilizing
the vegetative cover as the chief tool in conservation.

To understand the role of cover both as an object of conservation and
as the chief method in it, it has been necessary to turn to the life form and
life history of the major species, as well as to the dynamic processes con-
cerned in succession. For example, in the mixed prairie of the Great Plains,
each important species or dominant possesses its own habit of growth and
growth form, exerts its particular reaction upon the soil and upon water,
and manifests its own type of competition and cooperation with the as-
sociated dominants. They form an organic whole, in which no one part can
be changed or removed without affecting all the others, a principle that has
served to explain some unexpected results in attempting to modify or
restore cover in conservation projects. Succession, both climatic and edaphic,
is a universal and inescapable process, and its detailed course must be
understood to permit its control or guidance. The general significance of
all these features to the restoring of overgrazed pastures and to recovery
in abandoned fields has been pointed out in the previous report. During
the past year, much attention has been given to methods of supplementing

234 CARNEGIE INSTITUTION OF WASHINGTON

the natural processes by means of furrows and trenches, which promise to
shorten greatly the length of time necessary for succession.

The installation of the pasture furrow by the Soil Conservation Service
during the past four years has been carried out on such a vast scale, amount-
ing to many thousands of miles, that it has been possible to study its per-
formance in practically all the grassland communities. The results have
confirmed the assumptions drawn from the ecological investigation of
dynamic processes in each type. In a complete grass cover, the stems and
leaves intercept some part of the rain and together with the litter retard
movement so that nearly all the water is led into the soil by means of the
roots. Under such conditions, the silt and fine organic matter are held
in position to maintain the normal soil structure. Cover exerts a similar
control of the surface soil by reducing or eliminating the force of wind.
These desirable effects are diminished as the cover is impaired by grazing,
fire, or drought, and it becomes essential to reinforce the grasses by means
of mechanical aids.

The primary question thus becomes one of the size and spacing of the
furrow to be employed. Sheet erosion, gullying, and flooding must be pre-
vented, water and nutrients retained and absorbed into the soil, favorable
conditions provided for the germination of seed, and the soil disturbed as
little as possible, in order to prevent a succession of weeds. Large con-
tour furrows meet these requirements more or less imperfectly, since their
chief value lies in holding back heavy rains to prevent accumulation into
flood proportions. With spacings of 30 to 100 feet, too much water drains
into the ditch and away from the slope where it is needed, carrying with
it silt arid organic matter. The ditch first becomes a pond, then a mass
of colloidal material, and finally a miniature desert with an almost im-
pervious soil, in which seedlings soon perish. The ridge or berm washes
into the furrow on one side and over the grass on the other, and this bare
area becomes the site of a weedy growth, of little or no value as forage or
protection and barring out grasses by competition for a number of years
to come. When wheat grass or buffalo grass is present, a thin band of re-
generation may appear at the edges of the ditch and the base of the berm,
but this is of little importance by comparison with the width of the drained
interval. Furthermore, the amount of surface taken out of production by
furrow and ridge may exceed 20 per cent when the interval is 20-30 feet,
thus rendering the furrow still less adequate to the needs.

In the task of remedying the defects of large furrows, the experimental
plots have been based upon the assumption that the best device will hold
practically all the rain where it falls, at the same time preventing washing
of the fine surface material. Other desirable effects are to spread the soil
so that it serves as fertilizer instead of burying a wide band of cover, to
leave roots exposed in the trench to act as channels of absorption, and to
prune the roots and thus stimulate their growth. Finally, the shallow
trenches catch grass seeds and litter and form excellent seed beds. In the
initial tests, the intervals were set at 6, 3, and 1.5 feet, and the trenches
were respectively 6 X 4, 4 X 3, and 3X2 inches wide and deep. The out-
come indicates that the closest spacing produces the best results in accordance

DIVISION OF PLANT BIOLOGY 235

with the expectation, and that the larger dimensions are best for the trench,
depending in some degree upon soil and condition of cover. It has also
been found that much the most rapid recovery occurs when sod grasses
are present, and this suggests the desirability of transplanting wheat grass
or buffalo grass to treated areas where they are absent. In terms of time,
labor, and equipment, trenches or "corrugations" are superior to contour
furrows, and in maintaining cover, keeping out weeds, and hastening re-
covery they possess even greater values.

The study of the relation between cover and wind erosion has disclosed
several facts of direct bearing upon the question of the formation of loess
deposits. The current view is that the fine material was picked up by the
wind during drought in grassland and laid down several hundred miles to
the eastward. This theory has been invoked to support the assumption
that dust storms have occurred throughout the geological history of the
Great Plains and that man in consequence has little responsibility for the
recent ones. Through years of field work in the West, dust storms have
never been observed to arise from areas with good cover, even during drought
periods. Moreover, measurements of the reduction of wind velocity by
sparse covers of short-grass render it improbable that dust storms could
have come from anything but bare soil. Throughout the "Dust Bowl," the
dune ridges have been derived from fields abandoned during drought, and
they no longer move when a fair cover is restored. These new facts as
to wind erosion and loess deposits were tested in the course of a motor
trip to classical loess horizons in Iowa with Dr. Kay and Professor Phillips.
As a result, it was agreed that loess had not been derived from grassland but
originated from wind erosion on bare glacial outwash plains and valley
deposits.

HISTORICAL CLIMATOLOGY

A. E. Douglass

During the past year Dr. W. S. Glock has made detailed study of the
relation between ring growth and rainfall in the pine trees near Prescott
by correlation and trend coefficients (see Year Book No. 32, 1933). He
finds that correlation is strong when the ring growth is compared with the
rainfall for the preceding January, February, and April, using unsmoothed
data without lag. The month of March introduces erratic results. After
the data had been smoothed the best correlation with tree growth was found
in the rainfall from November to April, inclusive, with one-year lag. He
reports that in smoothed curves it is easy to pick out the correlations visually.

In the summer of 1937 important aid was received from the United States
Forest Service. This consisted of maps showing the location of the giant
sequoia stumps from which V-cuts have been made, and which have
contributed greatly to the study of ring growth. This includes the areas
in the vicinity of General Grant National Park, from which collections
were made in 1915, 1918, and 1919, and from the old Enterprise Mill
site near Springville, California, from which collections were made in 1919,
1925, and 1931. For aid in this matter we are indebted to the United
States Forest Service, Washington, D. C., and to Mr. S. B. Show, Regional

236 CARNEGIE INSTITUTION OF WASHINGTON

Forester in San Francisco, and Mr. J. E. Elliott, Supervisor of the Sequoia
National Forest. The stumps were identified by Dr. Glock in a series of
field trips on which he was made the guest of the Forest Service.

Publications

Carnegie Institution of Washington Publication No. 486, entitled Prin-
ciples and methods of tree ring analysis, by Dr. W. S. Glock, with a fore-
word by A. E. Douglass and a contribution by G. A. Pearson, was issued
on September 15, 1937. This forms a long-needed introduction to much
that has been published already on the subject of tree ring work. A pam-
phlet entitled Tree rings and chronology, by A. E. Douglass, was pub-
lished by the University of Arizona October 1, 1937, as a Physical Science
Bulletin No. 1, and gives a summary of tree ring work. Much attention
has been given to the possibility of publication by microfilm. Microfilm
copies of volumes I and II, Climatic cycles and tree growth, are now
available. 1 The photographic part of a fourth volume in the series on
Climatic cycles and tree growth has been prepared, containing a photo-
graphic ring chronology extending back to A.D. 11. These photographs
were made by H. F. Davis, and the dating and annotations entered by
the writer. It is proposed to make available also in this microfilm form
a very large collection of annotated photographs, thereby greatly increasing
the number of localities represented in the ring chronology of the last
1900 years.

Cyclic Analysis

In the Year Book reports for 1936 and 1937 mention has been made of the
application of cyclograph analysis to solar rotation studies in the Magnetic
Character Figure C and in comparisons between sunspot and calcium floc-
culus occurrences, and ultraviolet light and other forms of radiation. This
has brought to light the service which can be rendered by cyclograph
studies upon certain data which have only been examined heretofore by
harmonic analysis methods. No better illustration of this could be given
than the direct comparison between cyclograph and harmonic analysis of
the Magnetic Character Figure C for the years 1932, 1933, and 1934. When
minutely compared it is seen at once that the cyclograph, while showing
general results (as in harmonic analysis) for the length of solar rotation,
shows subordinate results at the same time; for example, in the same pat-
tern we get not only full solar rotation but the half-rotation also, and we
see the occurrence of certain phenomena in one solar longitude and the
occurrence of similar phenomena in the opposite solar longitude presented
toward the earth two weeks later. After these results have been obtained
by the cyclograph it has been perfectly easy to verify them fully by plotting
the location of observed maxima of the Magnetic Character Figure C on
a time scale and then adding the maxima of a fabricated curve based on
the hypothesis that the well-known six-months maxima alternate in opposite
solar longitudes. The two are found to agree.

1 Bibliofilm Service, Department of Agriculture, Washington, D. C. See list of Carnegie
Institution publications. Volume III of the above series and Dr. Glock's book just re-
ferred to are also available in that form.

DIVISION OF PLANT BIOLOGY 237

An addition has now been made to this kind of result by an analysis of
radio reception energy recorded by Dr. H. T. Stetson for the same years,
1932, 1933, and 1934. These radio reception data gave a pattern recognized
immediately as extremely similar to the pattern of Magnetic Character
Figure C. Amplitudes were large and small at the same time. Thus six-
months maxima showed in the radio reception as in the Magnetic Character
Figure data. When minute details of the patterns were compared it was
evident that the relation between these two phenomena was inverted, that
is, the reception energy increased with the decrease of the Magnetic Charac-
ter Figure C. A plot of the radio reception over this period of time compared
with a plot of the Magnetic Character Figure verified at once this strong
inverse relation.

In connection with these applications of the cyclograph to a field that
has been explored extensively by harmonic analysis, the former's great
advantage in getting almost instant results visually and its unique facility
in showing the time element in changing cyclic conditions have caused us
to regard the word "cycloscope" as fully applicable to the instrument.
For the sake of clarity the word "cyclic," meaning unstable cycle or dis-
continuous period, is being tried out elsewhere as a possible alternative for
the word cycle.

Staff

The three-year cooperative arrangement between the Carnegie Institution
and the University of Arizona came to a close at the end of 1937. How-
ever, Dr. dock's important work on the ring-rainfall relation at Prescott,
and other compilations that he was engaged on, were continued for another
half-year. During the last half of 1937 we enjoyed as before the courtesy
of the Desert Laboratory of the Carnegie Institution in Tucson. We of
the tree ring work express our deep appreciation for the many years of
aid from the Carnegie Institution. In the meantime, on December 4, 1937,
a Laboratory of Tree Ring Research was established by the Board of Re-
gents at the University of Arizona, where important parts of the tree ring
work will be continued.

PALEOBOTANY

Ralph W. Chaney

Studies of Cenozoic plants have continued along the lines described in pre-
vious reports and may be summarized as follows:

R. W. Chaney. In the spring of 1937, an invitation was received from the
National Geological Survey of China to cooperate with members of its staff
in a study of a recently discovered fossil flora from Shantung Province. Large
collections were examined during the summer in Peiping, and additional mate-
rial was secured during a short period of field work. Preliminary preparation
of the manuscript was carried on in cooperation with Dr. Hsen Hsu Hu,
Director of the Fan Memorial Institute of Biology. This flora represents
the first record of Miocene vegetation in China. It includes many plants
which are represented by related fossil species in the Miocene floras of
Siberia, Japan, North America, and Europe. From most of these floras it

238 CARNEGIE INSTITUTION OF WASHINGTON

differs in its absence of redwoods and other conifers, and in the greater
abundance of warm-temperate types, such as figs and laurels. Various con-
clusions are being reached regarding past migrations of forests in Asia, and
the climatic changes which caused them.

Recent collections from the Miocene on the west slope of the Cascade
Range in Oregon indicate a close similarity to floras of this age on the east
side of the mountains. It is concluded that the Cascades were not raised
up until near the close of the Miocene, and that broad valleys or embayments
were present along the Oregon coast in which elements of an earlier, less
temperate flora survived into this epoch.

D. I. Axelrod. Further studies of the Miocene and Pliocene floras of
California have indicated northward movement of a Mexican element dur-
ing later Tertiary time. The presence of this element in Tertiary deposits
in the western United States may be used as an indication of their late Mio-
cene or Pliocene age.

C. Condit. Several floras of Upper Miocene age from central California
indicate varied living conditions during this epoch, conditions which have
been greatly altered down to the present. A forest of bald cypress (Taxo-
dium) occupied the shores of what is now the San Francisco Bay area, while
in the hills to the east, the plants indicate a cooler and less humid environ-
ment.

E. Dorf. The study of a flora of Cretaceous age from the Medicine Bow
formation of the Rocky Mountain region has been completed. This flora
includes many plants unlike those now living, which is consistent with its
occurrence in rocks which were laid down before the modern development
of angiosperms. Studies are in progress which will throw further light on
the ancestry of Tertiary and modern floras of western America.

R. S. LaMotte. A supplement to Knowlton's Catalogue of the Mesozoic
and Cenozoic plants of North America has been prepared to include publica-
tions issued since 1919. In view of the extensive investigations which have
been carried on during the past twenty years, particularly in western Amer-
ica, this addition to the catalogue and bibliography will be of great value
to all paleobotanists.

H. D. MacGinitie. A continuation of the study of the Florissant flora by
Dr. MacGinitie has resulted in additional collections and the accumulation
of significant data regarding conditions of deposition of the volcanic shales
in which fossil plants are so abundant. This work has been carried on with
further financial support by Mr. Childs Frick, of the American Museum of
Natural History. Dr. MacGinitie has also continued his study of the Chalk
Bluffs flora on the western foothills of the Sierra Nevada. This represents
one of the largest and best-preserved Eocene floras in western America.

The Atomic-Physics Observatory, Department of Terrestrial Magnetism,

Washington, D. C.

DEPARTMENT OF TERRESTRIAL MAGNETISM1

John A. Fleming, Director
O. H. Gish, Assistant Director

SUMMARY

The report-year (July 1, 1937 to June 30, 1938) has been marked by ener-
getic prosecution of experimental investigation and continued coordination
and integration of various researches paving the way for more general formu-
lation of geophysical facts. Good progress has been made in two major
projects which open new fields of investigation and promise important ad-
vances. One of these is the completion of the Atomic-Physics Observatory
and the considerable progress in the installation of the electrical equipment.
The electrostatic generator and tube are designed to operate at potentials
exceeding five million volts and offer unique opportunity for further studies
in the expanding field of nuclear physics — a field to which we must look for
additional understanding of magnetic phenomena. The second project
realized is the installation of the automatic multifrequency equipments for
ionospheric measurements at both the Huancayo and Watheroo magnetic
observatories. This equipment, developed at the Department, has the fol-
lowing characteristics: ability to record successfully without interference
from existing radio services; relatively uniform vertical radiation through-
out the frequency-range ; automatic interlocking of transmitting and receiv-
ing tuning; mechanical simplicity and uniform limits of precision and resolu-
tion. The stations at Huancayo and Watheroo operating continuously in
conjunction with a somewhat similar equipment at the National Bureau of
Standards station at Meadows, Maryland, should provide a much more com-
plete survey of the upper atmosphere than has been previously possible.
Results at the Kensington Experimental Station of the Department in Mary-
land, where the apparatus was tested, appear to have gone a long way toward
settling the vexed question of the ionosphere and its refractive index for radio
waves, an uncertainty heretofore restricting our ability to interpret iono-
spheric observations.

Magnetic investigations. The outstanding advances in magnetic investi-
gations concern two distinct branches of the science: the rapidly varying
external field and the slowly varying, so-called permanent field. A procedure
was developed for separating the internal and external portions of a localized
varying magnetic field observed at the Earth's surface without recourse to
the use of spherical harmonics by assuming the Earth's surface to be an
infinite plane and employing solutions of Laplace's equation appropriate to
the case. This permits the hypothetical mapping of the magnetic field at
various heights, from which cogent inferences may be drawn regarding the
location of the processes giving rise to the magnetic effects. Further atten-
tion was devoted to the theory suggested in 1936 to account for auroral-zone
features of magnetic disturbance and for the average characteristics of mag-
netic storms in polar regions.

1 Address: 5241 Broad Branch Road Northwest, Washington, District of Columbia.

239

240 CARNEGIE INSTITUTION OF WASHINGTON

Measurements made on a sample of sediment extending 9 feet into the
floor of the North Atlantic Ocean show marked differences in the magnetiza-
tion at various depths. If correctly interpreted, these measurements indicate
that the direction of the compass in that region was about 60° east of true
north at the time the sediment was deposited many thousands of years ago,
whereas at the present time in the same locality it is 30° west of true north.
In further investigations of this nature, varved Pleistocene clay from beds
of old glacial lakes near New Haven, Connecticut, was collected for like
examination. This method of studying geomagnetism through the measure-
ment of fossil magnetization holds the hope of possible determination of
secular changes in geologic ages. A method of measuring the moment of
small magnetic dipoles was devised in this connection. The theoretical sensi-
tivity and practical application are such that moments of 3 X 10-T CGS
unit can be detected. Consideration was given to methods of interpreting
geological structures from their effects on the Earth's magnetic field as ob-
served at the surface, particularly for application in volcanic regions.

The weekly American magnetic character-figures (Ca) for the seven
American-operated observatories at Watheroo, Huancayo, Cheltenham,
Honolulu, San Juan, Sitka, and Tucson were compiled and published regu-
larly each week through Science Service. Statistical examination of the data
for the first year of this character-figure shows it to be a precise measure
and to represent worldwide conditions with relatively high fidelity. The
first six months of 1937 reveal a close relation to the international magnetic
character-figure adopted from the records of over forty observatories. It
appears that, while the international figure is superior for selecting extremely
quiet days, the American figure is superior for selecting extremely disturbed
days and for the study of radio-communication conditions. Studies of the
effect of magnetic activity on radio-transmission conditions showed the two
phenomena to be closely correlated, superior results being obtained by use
of the American magnetic character-figure.

Cosmic radiation. The investigation of a positive relationship of cosmic
radiation with magnetic and other phenomena was continued. Worldwide
decreases of 3 to 5 per cent in daily means of cosmic-ray intensity are found
to be associated with changes in the Earth's magnetic field during two major
magnetic storms; other magnetic storms of equal intensity occur with no
appreciable cosmic-ray effects. Thus it appears that the entire current-sys-
tem for the storm-time field of both types of storms cannot be located at the
same distance above the Earth. A significant correlation between changes
in daily means of cosmic-ray intensity for two stations separated 50° in
latitude probably results from the mechanism responsible for the magnetic-
storm effect. Statistical analyses of the cosmic-ray records obtained at
Cheltenham and at Huancayo proved inadequate to establish a sidereal
diurnal variation in cosmic-ray intensity.

Analysis of all available data from Cheltenham, Teoloyucan, Christchurch,
and Huancayo shows that the major changes in the 10-day means of cosmic
radiation are all worldwide. The correlation between the worldwide changes
at different stations was found high enough to provide important informa-
tion regarding their variation with latitude and altitude. It seems impos-

DEPARTMENT OF TERRESTRIAL MAGNETISM 241

sible to explain the annual waves found at these stations in terms of a solar
magnetic moment.

Terrestrial electricity. The rationale of the subject, atmospheric electric-
ity, was improved in several respects. For example, the observation that
the electrical conductivity of air at sea is relatively independent of latitude
was accounted for quantitatively. The quantitative dependence of air-
conductivity upon the intensity of cosmic radiation up to considerable alti-
tudes, especially over the oceans and the polar regions, was more securely
established. The electrical resistance of a vertical column of atmosphere,
as calculated from the observed intensity of cosmic radiation, was found
to be about 20 per cent greater at the equator than at 50° latitude. This
provides an acceptable explanation for the dependence of electric field-
strength upon latitude, which was shown by observations made on cruises
of the Carnegie.

It was found that condensation-nuclei (ultramicroscopic aggregates of
molecules upon which water-vapor readily condenses) are formed in air in
the laboratory by ultraviolet light. This observation strengthens the likeli-
hood that the stratum of nuclei — which was indicated by registrations of the
electrical conductivity of air, made on the stratosphere flight of the balloon
Explorer II, at an altitude of 18 to 22 km — is formed in this way, and that
the apparent association of nuclei and ozone is significant.

Observations of the apparent reflection of radio waves from relatively low
levels in the troposphere and stratosphere have been interpreted by some
investigators as evidence of very intense ionization at these levels. This
interpretation was shown to be inadmissible ; the ionization observed in these
regions is nine orders of magnitude less than that implied by that interpreta-
tion, and the energy required to maintain extensive layers of that character
is not available.

It was shown by an analysis of registrations of the electric currents in the
Earth at Tucson, Arizona, and at Huancayo, Peru, that the Moon exercises
a secondary influence on those currents, giving rise to a harmonic component
in the daily variation which has a period of 12 hours and an amplitude about
one-fifth to one-sixth that of the variation which follows solar time.

Ionosphere. Isolation of the radio fade-out effect in a particular region
of the ionosphere was accomplished using the powerful automatic multi-
frequency technique. The ionization in the outer atmosphere produced by
the ultraviolet light emanating from the bright chromospheric eruptions is
absorbed almost exclusively below the level of about 90 km. This con-
stitutes strong confirmatory evidence that the electrical currents causing the
diurnal variation in the Earth's magnetism must flow below this level. That
the ultraviolet radiation from the bright eruptions on the Sun is not absorbed
in the higher regions of the outer atmosphere in passing through them is new
evidence of the physical constitution of these regions, and of the processes
producing ionization in them. This provides a new approach to the study
of physical problems of the outer atmosphere and of the Sun.

Continual recording of the electrical state of the outer atmosphere is now
an accomplished fact at the magnetic observatories of the Department at
Huancayo and at Watheroo. Installation of the automatic multifrequency

242 CARNEGIE INSTITUTION OF WASHINGTON

equipment represents the culmination of a long period of research and devel-
opment by the Department to make possible a complete record of ionospheric
fluctuations. Thus the ionosphere — the region of transition in which many-
solar effects are translated into observed geophysical phenomena — is now
under continuous observation.

The experimental determination of the Lorentz polarization correction in
the ionosphere represents a major contribution to the field of classical physics.
The relation between the constitution of a conducting medium and its refrac-
tive index is a fundamental problem of physics to which attention has been
devoted for many years. Heretofore, no experimental determination of this
correction had been made, so that the experiments in the ionosphere repre-
sent the first factual evidence which has been brought to bear on the subject.

Nuclear physics. Studies in the laboratory of the primary particles of mat-
ter, which have magnetic properties as one of their very few attributes, were
directed chiefly toward accurate measurements of the large attractive forces
which operate inside the nuclei of all atoms. The Department's pioneer
measurements two years ago on these nuclear forces, which are neither gravi-
tational nor electromagnetic, but something "new," were amply confirmed
here and elsewhere, and are accepted as fundamental to any understanding
of the nature of matter and the primary physical forces. The observations
of this year, made with a different apparatus and completely independent
of the earlier series, served to calibrate all the measurements on an absolute
scale (centimeters, grams, seconds) as required for theoretical interpreta-
tion and universal applicability.

Instruments. The coil of the new primary standard for measuring in ab-
solute units the Earth's vector magnetic field was completed. It is con-
structed with an accuracy such that the magnetic field is calculated to about
one part in a million. The alidade and mountings for the coil are now under
way.

Observatory -work. The observatories at Huancayo, Peru, and at
Watheroo, Western Australia, continued the extensive geophysical program,
obtaining continuous records of magnetic elements. Magnetic activity was
very marked as the peak of the sunspot-cycle was reached during 1937. The
remarkable range of 1350 gammas occurred in horizontal intensity during
the exceptionally violent magnetic storm of April 16, 1938, at Huancayo.

Cooperative work was continued with the following observatories : Atmos-
pheric-electric program at Apia in Western Samoa ; atmospheric-electric and
earth-current programs at Tucson, Arizona; maintenance of international
magnetic standards at the Cheltenham Magnetic Observatory of the United
States Coast and Geodetic Survey. Some cooperation was extended to the
Magnetic Observatory at Cape Town through the loan of instruments and
information regarding methods. As a result of cooperation with the Mac-
Gregor Arctic Expedition, a temporary magnetic observatory was estab-
lished in September 1937 near Reindeer Point at Etah, Greenland.

Land-work. Field work in Australasia and the Pacific Islands was con-
tinued. Comparisons of observatory-standards were made at the Apia,
Honolulu, Watheroo, and Batavia observatories, and at Blacktown in Aus-
stralia (with the instruments of the Aerial, Geological, and Geophysical

DEPARTMENT OF TERRESTRIAL MAGNETISM 243

Survey of Northern Australia). Thirty-five stations were occupied in New
Caledonia, New Hebrides, Tahiti, Western Australia, Northern Australia,
Malaya, Siam, and French Indo-China. In cooperation with the Gulf Re-
search and Development Company, results at six stations in Arabia were
obtained.

INVESTIGATIONAL AND EXPERIMENTAL WORK

TERRESTRIAL MAGNETISM

Those more especially taking part in work reported under terrestrial mag-
netism include Berkner, Fleming, Forbush, Johnson, Johnston, Ledig, Mc-
Nish, Torreson, and Vestine. Dr. J. Bartels (in residence at Washington
July 23 to September 28, 1937) and Professor S. Chapman, research asso-
ciates, through constructive advice and their respective researches at London
and Berlin, took important part in the year's work.

PERMANENT FIELD

Heights of electric currents near the auroral zone. A mathematical method
for separating the internal and external portions of a local magnetic field was
developed. Incidentally, the solution leads to inferences regarding the height
and form of the origin of the magnetic field.

Assuming the Earth to be an infinite plane, variations in potential may
be represented by the equation

W = Fe{x,y,z) + Ft(*,y^)

for all points in and close to the plane, the subscripts e and i referring to
portions due to origins above and beneath the surface, respectively. Appro-
priate series-solutions of Laplace's equation are selected to represent the
potential, subject to the condition that Fe(x,y,z) vanish at z = — oo and
Fi(x,y,z) vanish at 2 = + °°> the same functions being used for both the
external and internal portions. Appropriate derivatives of W are the com-
ponents of magnetic intensity. The coefficients of the two potential-func-
tions, external and internal, are additive in the differentiation with respect
to x and y but they are subtractive in the differentiation with respect to z,
owing to the imposed condition regarding vanishment. As in the theory of
Gauss, parameters in series selected to fit the variations in horizontal inten-
sity are sums of the external and internal coefficients, while those for the
variations in vertical intensity are their differences. The external and in-
ternal coefficients may then be determined by solving pairs of simultaneous
equations.

The external and internal portions may be evaluated at various levels
above or below the plane where the field is observed, which evaluation is
valid provided it is not conducted for a level equal to or above that at which
the magnetic field originates. With increasing distance from the plane
higher-order terms in the potential-series assume increasing importance so
that at some level convergence of the series becomes very poor. This level
is taken to be the upper limit for the location of the origin of the potential.

Application of the method to a particular magnetic disturbance indicated

244 CARNEGIE INSTITUTION OF WASHINGTON

it was due primarily to a flow of current westward along the auroral zone
in a sheet about 700 km wide located at a height between 100 and 150 km, the
currents induced within the Earth being found comparatively unimportant.
Previous estimates for similar currents indicated wide ranges of heights
varying between 100 and over 1000 km.

Electromagnetic measurement of rock-magnetization. Numerous measure-
ments and important improvements in method were made to determine the
magnetization of rocks. The equipment described in last year's report is now
adequately sensitive to meet expected requirements. Measurements made
on several of the cores taken from the North Atlantic by Dr. C. S. Piggot
of the Geophysical Laboratory gave encouraging indications. Tests on the
Pleistocene varved clays from glacial lakes in New England show it is worth
while to study them magnetically. Continuation of these researches promises
results of fundamental importance to terrestrial magnetism and geology. So
far all evidence suggests that sedimentary deposits retain the magnetization
which was imparted to them by the Earth's magnetic field, presumably at
the time of their deposition. Conclusive information on this point will be
secured from tests on collected samples of varved clays. If these tests are
affirmative, then a means is afforded for tracing changes in the Earth's mag-
netism back through geologic ages as accurately as the rocks are dated, and
a new means of dating geological specimens, namely by their magnetization,
may be available.

For tests the specimen is clamped to a disk of wood mounted on a verti-
cal shaft and is rotated at a speed of ten revolutions per second in a coil
wound on a bakelite form mounted in an aluminum box to shield from stray
fields. Electromotive forces induced in the coil by the rotating specimen
are amplified and rectified by a synchronous commutator geared to the driv-
ing shaft and then measured by a sensitive galvanometer. By rotating the
brushes on the commutator so that a zero-reading is obtained the direction
of magnetization may be determined, while the intensity of magnetization
is determined by the maximum deflection. A small test-magnet mounted in
a bakelite block is used for calibration. Effects produced by vibration of
the coil in the Earth's field are eliminated by having a second layer on the
coil wound in the reverse direction. The theoretical limiting sensitivity of
the apparatus is the detection of an intensity of magnetization of 8 X 10— 8
CGS in a cubical specimen 15 mm on each edge, although practical limita-
tions are set by finding material for the rotating mechanism which is less
magnetic than the specimen to be tested.

Extensive tests were made on several cores taken from bottom-deposits of
the North Atlantic by Dr. C. S. Piggot of the Geophysical Laboratory. Core
no. 3, taken off Newfoundland, consists of a finely divided material known as
blue mud. Changes in magnetic declination as great as 90° and consistent
through the core were measured. If these changes correspond to real changes
in the Earth's magnetic field they exceed any which have been recorded in
historic times, although they are not so great as to cast doubt on their reality.
Changes as great as 36° in declination have been recorded at London during
two centuries. It has been estimated that this particular core represents
sediments deposited over several thousands of years.

DEPARTMENT OF TERRESTRIAL MAGNETISM 245

Tests made upon two cores taken within about 100 miles of each other
in the middle of the Atlantic gave inconclusive results. They contained many
pebbles, so that satisfactory specimens could not be cut from them. Existence
of these pebbles, which were too large to be aligned by the Earth's field as
they settled upon the bottom, would give rise to erratic directions of mag-
netization such as were observed. Portions of these cores which were suffi-
ciently homogeneous to permit fairly reliable measurements gave fairly con-
cordant results. Core no. 13, taken near the coast of Ireland, could not be
tested because of the extreme friability of the material and presence of
pebbles.

Measurements were made on a sample of varved Pleistocene clay from old
glacial lakes near New Haven and showed this clay sufficiently magnetic
to permit analysis. Therefore some 200 varves were collected in June 1938
from the same region for detailed examination. These samples were col-
lected in brass troughs with great care following the method employed by
Antevs in developing the chronology of the deposits, and with definite refer-
ence to the geographical and prevailing magnetic directions.

Interpretation of geologic structures from anomalies in terrestrial mag-
netism. Methods for interpreting geologic structures from magnetic anoma-
lies produced by them at the Earth's surface were investigated. Conven-
tional methods were extended and more powerful techniques considered.
These were tried on several hypothetical cases and gave remarkably deci-
sive results. The methods were developed particularly for application in
volcanic regions.

Map of secular variation. A world-map of secular-variation activity was
constructed for the interval 1885 to 1922. It differs from others in that it
shows isopors for the magnitude of the total-change vector, regardless of sign
or direction. Most maps show secular change in only one element or several
elements superposed, and since secular change in vertical intensity must
have a minimum where secular change in horizontal intensity or declination
has a maximum, interpretation of the maps is difficult. This map shows
again the fact brought out by Fisk that most secular-change activity occurs
in that portion of the Earth which is assumed to have a granitic crustal
layer; the Pacific Ocean is remarkably free from secular-change activity.

COSMIC RELATIONS

Solar and terrestrial relationships. The report-year has been of unusual
interest for the study of solar and terrestrial relationships, and of the rela-
tions between terrestrial magnetism and other phenomena, such as cosmic
radiation. In a steep increase since the last sunspot-minimum of 1933.8,
solar activity, as expressed by the relative sunspot-numbers, reached 114 in
the annual mean for 1937, a value which exceeds considerably any annual
mean since the high sunspot-maximum of 1870. The intensity of magnetic
disturbance followed this increase, and the year 1937 appears to be the most
active year for over 60 years, although no individual storm of outstanding
intensity occurred in 1937. But January 1938 was marked by three suc-
cessive storms. A violent magnetic storm of exceptional character on April
16, 1938, was preceded 21 hours before by an exceptional eruption observed

246 CARNEGIE INSTITUTION OF WASHINGTON

on the Sun's surface. Because of the well-known lag of magnetic behind
solar activity, it is quite likely that the lull of magnetic disturbance expe-
rienced in June 1938 will be only temporary, and that the harvest of mag-
netic storms for the study of their general features, their individualities, and
their variable effects on the ionosphere and cosmic radiation will increase
in the next year.

In conjunction with a research student, A. J. Majid Mian, Chapman is
attempting to express the daily variation of monochromatic ion-production
and ion-content in the atmosphere, in terms of a Fourier series, and, further,
to express the geographical distribution of these quantities in terms of spheri-
cal harmonics ; some progress is being made in this rather difficult investiga-
tion which should assist in future attempts to perfect the theory of the daily
magnetic variations.

Geophysical lunar almanac. The investigation of solar and lunar effects
is recognized as a major approach in the discussion of geophysical phe-
nomena. But apart from the well-known case of the oceanic tides, lunar
influences have been studied by comparatively few, although the large-scale
experiments performed daily by the Moon on the Earth are so much simpler
in character — purely gravitational — than those performed by the Sun. This
is largely because the magnitude of the lunar effects, with notable exceptions,
is usually only a very small percentage of the total variability, so that much
observational material must be used and a special statistical technique must
be developed to obtain reliable results.

Investigators in this field have keenly felt the lack of auxiliary tables
giving the motion of the mean Moon in a manner suitable for geophysical
work; thus, many calculations have been based on the convenient data for
the apparent Moon, furnished by the astronomical yearbooks. This expe-
dient has, however, the serious drawback that the connection is lost with the
harmonic analysis of the tidal force which is an adequate description for that
complicated time-function and is based on the mean Moon; furthermore,
the unequal length of the apparent lunar day is troublesome in the calcula-
tion. For this reason, the geophysical lunar almanac was prepared by Bar-
tels with the collaboration of G. Fanselau; it gives, for each day from 1850
to 1975, the phase of the mean Moon, its distance from mean perigee, and
the mean ascending node of the Moon's orbit. It is hoped that this almanac
will help to establish more uniformity in lunar geophysical work.

The work supervised by Chapman in the computing bureau on lunar varia-
tions in magnetic and barometric data went on actively and some progress
was made in preparing for publication.

Cosmic-radiation relations. Recent investigations of the data from cos-
mic-ray meters at Cheltenham, United States, Teoloyucan, Mexico, Christ-
church, New Zealand, and Huancayo, Peru (the last practically on the mag-
netic equator) have shown that after a 12-month wave is removed from the
data at each of these stations except Huancayo, which shows none, the
means of cosmic-ray intensity for each one-third month are remarkably simi-
lar at all stations. The high correlation between these worldwide changes
in cosmic-ray intensity at any two stations is exceeded by few, if any, geo-
physical phenomena measured at such widely separated stations. The char-

DEPARTMENT OF TERRESTRIAL MAGNETISM 247

acter of these worldwide changes is such as to suggest the continual existence
of equatorial ring-currents with changes in intensity or radius. This sup-
position is strengthened by a strong 27-day recurrence-tendency in the cosmic-
ray data. The variation of magnitude of the worldwide effect in cosmic-ray
intensity with altitude and latitude indicates that the continued existence of
ring-currents may have important consequences in the interpretation of the
latitude-variation of intensity at extreme altitudes. A quantitative theory
for the explanation of the worldwide changes in cosmic-ray intensity may
also be expected to disclose the fundamental mechanism causing magnetic
storms. The quantitative results of cosmic-ray investigations provide excel-
lent material for checking a quantitative theory for the worldwide effect.

MAGNETIC DISTURBANCES

Average worldwide changes during magnetic storms. The average world-
wide changes in the Earth's field during magnetic storms, additional to those
present on magnetically quiet days, were investigated using extensive new
data of the International Polar Year, 1932-1933, in continuation of a study
undertaken under the supervision of Chapman. The average characteristics
of disturbances given by observation were shown to be in good qualitative
and quantitative agreement with the worldwide atmospheric-electric current-
system of magnetic storms proposed by Chapman. If these electric currents
flow in closed circuits in the atmosphere their height is deduced as roughly
100-150 km. The electric current-system proposed by Birkeland was shown
to be inconsistent with observation in several important respects. In low
latitudes of the Earth it is also possible that the storm-time variation is due
mainly to an encircling ring-current in the equatorial plane, in which case
its radius computed from the magnetic data was found to be about two to
four times that of the Earth.

Average characteristics of magnetic storms asymmetrical relative to the
centered dipole of the Earth's magnetic field. This investigation is a sequel
of the foregoing. Since magnetic disturbances appear with highest intensity
in the region very near the auroral zone, the magnetic data were used to give
a new and improved determination of the geographical position of this zone.
The auroral-zone curve of terrestrial magnetism, in north polar regions, is
oval, almost elliptical, and shows asymmetry relative to the centered dipole.
It agrees roughly with the curve of maximum auroral frequency as derived
by Fritz, except in regions where his auroral data were scanty.

The average disturbance diurnal variation of magnetic storms is mainly
sinusoidal in character. Little or no significant dependence of the amplitude
of the disturbance diurnal variation upon longitude was found. The ampli-
tude is approximately symmetrical about the geographic equator, is zonal-
symmetrical with respect to the auroral zone, and has a zero vertical com-
ponent near the north pole given by the eccentric dipole most closely repre-
senting the Earth's field. Induced electric currents flowing in the oceans
appear to contribute little to the diurnal variation. In general, the local
time-phase of the variation shows an average range of about four hours along
parallels of geomagnetic latitude. The time-phase depends closely upon the
magnetic time (referred to the north pole given by the eccentric dipole) for

248 CARNEGIE INSTITUTION OF WASHINGTON

intense disturbances appearing at the auroral zone. This suggests that the
electric currents causing this diurnal variation are generated near the auroral
zone, and an investigation is under way to determine whether currents initi-
ated in this way would give rise to an electric current-system compatible
with observation. The asymmetrical characteristics of magnetic disturbance
are also compared with those shown by aurora.

Origin oj magnetic disturbance in polar regions. It is believed that most
of the phenomena can be accounted for by means of a dynamo-theory similar
to that proposed by Chapman in 1918 and subsequently extended in 1936 at
this Department to account for magnetic "bays." A brief outline of the
present trend of this theory follows: Impact of corpuscles, giving rise to
auroral phenomena, along the auroral zone in the region between midnight
and dawn causes expansion of the upper atmosphere and consequent genera-
tion of electromotive forces through vertical motion of atmosphere across
the horizontal component of the Earth's permanent field. This gives rise
to a westward current along the auroral zone which closes through low lati-
tudes and across the polar cap. A collapse of the expanded atmosphere on
the opposite side of the auroral zone causes eastward currents in a similar
manner with corresponding closures.

During the past year V. C. A. Ferraro renewed his cooperation with Chap-
man in the attempt to construct a deductive theory of magnetic storms and
auroras by developing and improving the theory they published some years
ago. Progress in this work strengthens the hope that this theory is on gen-
erally right lines.

MAGNETIC ACTIVITY

B artels computed the final ^-measure of magnetic activity 1935 and 1936,
and preliminary values through April 1938. Three storms in January 1938
gave the high value u = 2.74, while the annual mean for 1937 reached 1.38;
this exceeds the highest annual values of u reached during the last five sun-
spot-maxima (1.18 in 1926, 1.23 in 1919, 0.98 in 1909, 1.33 in 1892, 1.22 in
1882). This variable intensity of the maxima in the 11-year cycle has a
counterpart in the different degree of terrestrial-magnetic quietness reached
during the sunspot-minima. Since the last-mentioned differences appear
more marked in the magnetic data than in the relative sunspot-numbers —
the minima of 1901 and 1913 were appreciably quieter in magnetic respect
than those of 1923 and 1933 — a special study was made to ascertain whether
these differences were real and not due to some fault in the measure of ac-
tivity. It appeared that the magnetic evidence is conclusive, and that it is
in conformity with solar observations in so far as the Sun was entirely free
of spots on more days around 1901 and 1913 than around 1923 and 1933.

Character-numbers for magnetic disturbances. In connection with the vari-
ous proposals for the adequate description of magnetic disturbances, Bartels
formulated a Potsdam Magnetic "Kennziffer" (K) . Its main difference
from existing international and American (Ca) character-figures is the divi-
sion of the Greenwich day into eight intervals of three hours each. Such a
shorter interval seems more suitable because of the difficulty experienced in
ascribing a single figure to a day or a half-day in which the degree of dis-

DEPARTMENT OF TERRESTRIAL MAGNETISM 249

turbance may vary considerably; on the other hand, a further subdivision
(hourly intervals) would add greatly to the labor involved without propor-
tional gain to justify it. K consists of two figures; the first, varying from
0 to 9, indicates the highest amplitude in the deviations of one of the three
magnetic-force components from a smooth diurnal variation, while the
second indicates the form of the variations (pulsations, bays, storms) . So
far, the definition of K has been chosen so as to give a good characterization
of the records of Niemegk Observatory ; the experience gained there should
advance discussions for an international code.

ARCHIVES OF MAGNETIC RECORDS

Polar-Year magnetic records. The Department now has on file most of
the special records made during the Second International Polar Year. Nearly
1000 miniature film-records have been received from the Central Bureau
of the Polar Year Commission at Copenhagen, Denmark. Each film gives one
month of daily records from one observatory. A special apparatus was pur-
chased to permit rapid and accurate reduction of these records for special
investigation.

Solar photographs and sunspot-charts. . The United States Naval Observa-
tory supplies the Department prints of its daily solar photographs for use
in studying and anticipating magnetic disturbances. In several cases these
have permitted forecasts of magnetic disturbances so that the Department
was able to supply information whenever requested by persons engaged in
radio work or cosmic-ray research. These photographs are supplemented by
carbon copies of the charts of sunspots made daily at the Mount Wilson Ob-
servatory, which are received some time later.

INSTRUMENTAL DEVELOPMENTS

CIW induction-variometer. The CIW induction-variometer for measur-
ing time-variations in the vertical component of the Earth's magnetic field
was kept in continuous operation by the staff of the Cheltenham Magnetic
Observatory of the United States Coast and Geodetic Survey. During its
last period of operation extending over two years no sudden changes in base-
line or sensitivity have occurred such as are common to most instruments
of the "knife-edge" pattern. Despite excessive ranges of several severe mag-
netic storms, the variometer returned to normal values without any evidence
of having been affected. Base-line drift, which was rather great when the
instrument was first installed, has diminished continually. Experience thus
proves the practicality and superiority of this instrument for use at ob-
servatories.

Electromagnetic methods. Johnson continued the design and construction
of the coil-form of the new CIW primary standard for measuring the Earth's
magnetic vector (see Year Book No. 36, pp. 11-13). The actual construc-
tion of the coil, the most difficult part of the standard, is now completed.
The grooves in the pyrex coil-form were ground by means of a cast-iron lap
and fine emery, using optical methods of grinding, in a room kept at a con-
stant temperature of 26° C and 100 per cent humidity during grinding to

250 CARNEGIE INSTITUTION OF WASHINGTON

avoid variations caused by temperature and by evaporation. To measure
the diameters along the coil a mechanically operated micrometer was built,
in which the time of contact is signaled electrically; its sensitivity is greater
than 0.1 micron. Measurements on the diameter of coil were made to ±0.25
micron. The measurements on the coil itself show that it is cylindrical to
±0.5 micron or better, and uniform along the axis of the cylinder to ±1
micron or better.

The wire used in winding the coil is uniform to a few tenths of a micron
and was wound on the coil with uniform tension. A test of the uniformity
shows that the wires in place on the coil-form are all uniform to within about
±0.5 micron.

The method of measuring small magnetic moments was fully developed
during the year and was applied to the measurement of the polarization of
sedimentary deposits from the bottom of the Atlantic collected by Dr. Pig-
got of the Geophysical Laboratory.

In connection with the development of the alternating-current voltage-
measurements from the rotating coil of the primary standard, the limitation
of alternating-current voltage-measurements due to a statistical source in
the circuit in which a signal-voltage is to be measured was calculated theoret-
ically and was determined experimentally. It was found that the limit of
measurement was not dependent on the band-width of the amplifier, as has
been previously supposed, but depends only on the time of measurement and
the amount of the statistical voltage. From the analysis it becomes evident
that for a given circuit the use of alternating-current amplification yields
no theoretical increase in sensitivity over direct- current methods of measure-
ment, although in many particular problems alternating- current methods offer
great advantages. This result has been applied in the case of the measure-
ment of small magnetic moments as well as to the case of the primary
standard. The analysis also applies in the case of the searchlight-experiment
and has numerous other practical applications of general interest.

Some preliminary experiments were made with a flickering searchlight-
beam for investigating the upper air by Johnson, Meyer, and Tuve in col-
laboration with O. R. Wulf of the Fixed Nitrogen Laboratory. Although the
experiments were not conclusive, the light scattered from low heights was
measured and the method was shown to be practical. Chapman in England
in conjunction with A. Hammad made some progress in the study of secondary
scattering of light in the atmosphere.

PUBLICATIONS

The bibliography given below lists the Department's communications on
geomagnetic investigations during the year. At the suggestion of Chapman,
his colleague A. T. Price is preparing a book on electromagnetic induction
with geophysical and electrotechnical applications; it is hoped to include in
it an account of the work, mentioned in last year's report, by M. A. El Wakil,
on Rolf geomagnetic pulsations and their primary and induced current-
systems.

DEPARTMENT OF TERRESTRIAL MAGNETISM 251

TERRESTRIAL ELECTRICITY

The electric phenomena and properties of the atmosphere (atmospheric
electricity) and those of the Earth (geoelectricity) are comprised in the
subject of terrestrial electricity. Investigations of one or more aspects of
these subjects were pursued at Washington during the year by the following
persons: Gish, Mauchly (temporary assistant, June 28 to September 15,
1937), Rooney, Sherman, Torreson, and Wait, and Dr. R. Gunn as research
associate from May 3, 1938.

ATMOSPHERIC ELECTRICITY

Investigations in atmospheric electricity, although often of interest in
themselves, are largely directed toward a search for the mechanism by which
negative electricity is supplied to the Earth at an average rate of about 1800
amperes for the whole Earth. The source of this supply-current has thus
far escaped definite detection, but study of the current of positive electricity,
which flows from air to Earth in all areas where fair weather prevails and
which can be measured, leads to the foregoing estimate of the supply-current
magnitude and shows that it undergoes a fairly regular variation during the
day. Whether and in what manner it varies during the year and from year
to year is not clearly established, except that such variations, if existent, are
largely of the nature of oscillations about some mean value. Perhaps the
supply-current is generated in areas of storm, but, because of the great ob-
stacles to the making of suitable measurements there, this surmise has not
been adequately tested by direct observation of the current in such areas.
It is rather studies of the electric current in areas of fair weather which
thus far have provided most information regarding the supply-current. These
consist in measurements of the electric field and of the electrical conductivity
of the air. Most of the investigations of the report-year pertain to agencies
which affect the conductivity and thereby give rise to variations from time
to time and from place to place in the electric conduction-current from air
to Earth in areas of fair weather. These investigations are outlined more
specifically in the following paragraphs.

Ion-forming and ion-destroying agencies. The concentration of the ions,
upon which the conductivity of the air depends, is determined by the rate of
formation, the rate of destruction or transformation, and the migration of
ions. Wait and Torreson continued the continuous registration of large,
intermediate, and small ions, and the rate at which ions are formed in a
very thin-walled vessel at Washington. This was done in a well-ventilated
room of the absolute observatory until December 30, 1937, and thereafter
in a sealed room of the main building using two ionization-apparatuses. In
conjunction with these registrations, manual observations of the concen-
tration of Aitken nuclei, from which large ions are formed, were also made.
In the sealed room the contribution of nuclei and large ions from the human
breath was further studied.

Examination of the records obtained in the sealed room showed that the
large-ion and small-ion content of the air in the room responded to occupancy
in a manner similar to that found from earlier work. In addition, and of
particular interest, was the discovery that the ion-production as represented

252 CARNEGIE INSTITUTION OF WASHINGTON

by the measurements with the thin-walled chamber also shows response to
occupancy, the ionization being smaller when the building is occupied than
when it is vacant. This result is not explainable from our present knowledge
of the subject, and requires further investigation.

In November and December 1937, while ionization-apparatus 1 retained
its thin wall of cellophane, the wall of apparatus 2 was thickened by coating
the cellophane wall with paraffin. From the different results obtained under
these different conditions of operation it was possible to derive the amounts
of ionization contributed by the different types of radioactive radiations,
cosmic radiation, and residual or wall ionization.

In May and June 1938, the ion-counters were used for various tests bearing
on the question as to whether or not ions are produced when ozone is exposed
to light of short wave-lengths. The study of ionization of ozone is one line
of attack on the problem of how those radio fade-outs which accompany solar
eruptions are produced. Radio fade-outs accompanying bright chromo-
spheric eruptions on the Sun appear to be due to increased ionization in the
upper atmosphere at levels between 60 and 100 km, below the E-, Fx-, and
F2-regions of the ionosphere. It seems necessary to explain the increased
ionization between 60 and 100 km through the absorption of solar radiation
by some constituent of the atmosphere that does not exist at the higher levels
of the recognized ionospheric regions. It appears possible that ozone, which
is present in the region between 60 and 100 km, may be decomposed through
the absorption of radiations which lie in the range of 2800 to 2200 A, and
that through the process of decomposition ionization occurs. This would
afford a simple explanation of fade-out ionization which accompanies bright
chromospheric eruptions. To what extent ionization does accompany de-
composition of ozone can be determined through experiments in the labora-
tory, and preliminary tests relating to this matter were made by Wait and
Torreson with ion-counting apparatus in the sealed room.

In these tests, a mercury-arc quartz lamp was operated in the room. The
results show that when the mercury-arc lamp is operated, a large number of
large ions appears and, when the lamp is cut off, these large ions disappear
only gradually from the atmosphere, requiring a period of several hours to
do so. Small molecular ions must also be produced in enormous quantities,
but the small-ion counter shows only a moderate increase in number since
the small ions can persist only an extremely short time before they either
are caught by the great number of large ions already present or themselves
grow into large ions. Certain of the tests with the mercury-arc lamp showed
that the large ions result from the action of the radiations from the lamp
on some as yet undetermined material in or of the atmosphere, and are not
particles given off directly by the lamp itself. Tests were next made with
the mercury-arc lamp replaced by ionium as the ionizer, the ionium being
placed at the intake of the counters. It was found that the small molecular
ions produced in considerable quantities by the ionium did not grow in
their progress through the ion-counting apparatus; neither the intermediate-
ion nor the large-ion content showed any increase during the periods (some
of half an hour or more duration) when ionium was used as the ionizer.
Experiments are now in progress to determine if the small molecular ions

DEPARTMENT OF TERRESTRIAL MAGNETISM 253

produced by the mercury-arc lamp grow into large ions, and might thus
account for the numerous large ions which always come into existence a frac-
tion of a second after the lamp is put into operation. Information on this
point is an important requirement toward the solution of the main problem.

Experiments to test more thoroughly the reliability and characteristics of
apparatuses used for the measurement of air-conductivity and of the con-
centration of small ions were made by Sherman. These verified previous
conclusions, based on less exhaustive tests, namely, that the conductivity-
apparatus, as generally used in the work of the Department, yields accurate
results and that the values measured with the ion-counting apparatus require
a correction when intermediate ions are present in sufficient concentration.
The only unexpected result of these experiments was that quite appreciable
errors in the ion-count may be produced when the observer sits at the instru-
ment throughout the time required for a measurement. This is due to the
great number of nuclei and large ions which are introduced into the air from
the breath of the observer. A very gentle breeze is, however, sufficient, when
properly directed, to obviate this source of error.

The expressions which have been deduced for the relations between the
ion-forming and ion-destroying or ion-transforming processes have been re-
ported to be in disagreement with the facts in some cases. Several of these
cases were examined by Gish, who found that, by a suitable adjustment of
the coefficients in the expressions, agreement is obtained. This and other con-
siderations indicate that the coefficients which have been previously employed
are not generally applicable.

The observations of nuclei made at 8h each day at Huancayo, and studied
by Torreson during the year, provided a clue which, together with meteoro-
logical and other data, enabled Gish to devise a satisfactory explanation of
the remarkable contrast between day and night in air-conductivity and elec-
tric field-strength observed at Huancayo, Peru, especially during the dry
season (May to September, inclusive). At night, conductivity there is quite
large and potential-gradient small, but within nearly an hour centering at
about 7h the conductivity suddenly decreases to one-fourth or one-fifth the
night-time values while potential-gradient increases in a corresponding man-
ner. The change in the evening from day to night conditions is more gradual.
Meteorological observations indicate that a shallow surface-stratum of air
develops at night. The concentration of nuclei in this stratum is doubtless
relatively small because in its stable condition there is little mixing with the
overrunning general circulation which brings the nuclei from a distant source.
To test this explanation, measurements of the concentration of nuclei at
night as well as in daytime are required.

Ionic concentration and air- conductivity in the troposphere and strato-
sphere. Measurements of air-conductivity in the free atmosphere to an alti-
tude of 22 km, made on the flight of the stratosphere balloon Explorer II,
when compared with measurements of cosmic radiation led Gish and Sher-
man to conclude (see annual report for 1935-36) that the coefficient of recom-
bination between small ions varies directly as the pressure to the one-third
power, instead of the first power as usually assumed. Investigation of the
variation of that coefficient with pressure for ions in oxygen, made by

254 CARNEGIE INSTITUTION OF WASHINGTON

Gardner in Loeb's laboratory at the University of California and reported
during the past year, seem to support that conclusion for the range of pres-
sures encountered on the ballon flight. This strengthened confidence in cal-
culations of conductivity from observations of cosmic-ray intensity. It ac-
cordingly seemed worth while to make such calculations for different latitudes
since the cosmic-ray intensity at the surface depends somewhat upon latitude
but more especially because the variation with altitude shows a pronounced
dependence upon latitude. The calculations made by Gish and Sherman indi-
cate that the conductivity at the surface over the oceans, where ions are
produced almost exclusively by cosmic radiation, is on the average nearly
independent of latitude, the higher temperatures at the low latitudes prac-
tically counteracting the smaller intensity of cosmic radiation there. From
the calculated conductivity at all altitudes the resistance of a vertical column
of atmosphere of unit cross-section was calculated. This is an important
datum for various considerations in atmospheric electricity. It was found
to be about 20 per cent greater near the equator than at about 50° latitude.
The calculation of conductivity at the surface is consistent with observations
of conductivity made on the Carnegie over the oceans in that those observa-
tions showed no dependence on latitude. The contrast in columnar resistance
at high and low latitudes is quantitatively consistent with the smaller values
of gradient observed at low latitudes during cruises of the Carnegie and pro-
vides an acceptable explanation of the latter observation.

The interpretation by Gish and Sherman of registrations of air-conduc-
tivity made on the flight of Explorer II also indicated that, although Aitken
nuclei occur in negligible quantity in the altitude range 6 km to 18 km, yet
from 19 km to 22 km they are present in sufficient abundance to reduce the
air-conductivity to less than half the value which is to be expected in pure
air at the highest altitude of the observations (22 km) . This bank of nuclei
apparently coincides in position with a corresponding bank of ozone. That
this correspondence may be significant is indicated by the observations of
Wait and Torreson that Aitken nuclei are formed in great abundance by
the ultraviolet light from a quartz -mercury vapor lamp.

Although it is now established that a decrease in the intensity of cosmic
radiation sets in at some altitude (16 km near the equator and about 24 km
at 51° north magnetic latitude), yet, as proved by Gish and Sherman, the
conductivity cannot decrease with altitude at any altitude unless some factor
other than the observed decrease in cosmic-ray intensity is involved. From
this and other considerations it now seems likely that there are factors, such
as Aitken nuclei, which generally reduce the conductivity, in parts of the
stratosphere, to values lower than those usually estimated. However, pre-
liminary investigations of the effect of local pollution on the air-earth current
led Gish to conclude that neither this nor other factors acting in the unex-
plored levels of the atmosphere can contribute as much as 50 per cent to the
total resistance.

Some support for the foregoing conclusion is also provided by investiga-
tions by Sherman of the electrical conduction-current at College, Alaska,
during the International Polar Year. The average magnitude and the
diurnal variation of the current there is very near to that observed over the

DEPARTMENT OF TERRESTRIAL MAGNETISM 255

oceans, especially for the winter months at College. From this it is to be
inferred that the columnar resistance at College, especially in winter, is
about the same as the average over the oceans and, if it varies during the
day, the diurnal variation is the same.

Various observers have reported evidence that radio waves are returned
from the troposphere and lower stratosphere. This has been interpreted by
some investigators as pointing "to continuous ionization in sharply bounded
thin strata, over long periods of 5 X 1012 ions/cc or more in regions around
six to ten km ... at all times of day, in summer and in winter." However,
Gish and Booker pointed out that direct observations of the electrical state
of the troposphere and lower stratosphere show that the electrical conduc-
tivity of these regions is something like nine orders of magnitude less than
that suggested by those investigators. For example, continuous records of
electrical conductivity obtained on the flight of the Explorer II up to an alti-
tude of nearly 22 km show a maximum ionic density of only 5300 ions/cc
(at 14.8 km). Other observations from balloons show no trace of ionic
densities far in excess of 400 ions/cc throughout the troposphere. This evi-
dence is further supported by the continuous records of air-conductivity
obtained for 13 years at the Huancayo Magnetic Observatory, 3.3 km above
sea-level. Moreover, they show by calculations that the power required to
maintain the ionic concentration postulated in that interpretation is startling
when compared with that available from the Sun and thunderstorms. They
further conclude that the strength of radio echoes from the troposphere
would seem to have been greatly overestimated.

The electrode-effect in the atmosphere. For the normal electric field the
charge on the Earth's surface is negative, so that positive ions in the atmos-
phere drift toward the Earth while negative ions are repelled. Since nega-
tive ions apparently do not issue from the Earth to replace those which are
repelled, the concentration of negative ions in the air near the surface is, with
rare exceptions, less than that for positive ions. This is designated the
electrode-effect. The most general mathematical theory of this thus far
developed rests on some simplifying assumptions, the importance of which
it is desirable to test by observed data. This was done by Sherman using
measurements of positive and negative conductivity and of potential-gradient
made at College, Alaska, during the Second International Polar Year. There
is very little wind at that place in winter, so that the rate at which the air is
mixed by turbulence is correspondingly small. In that season he found fact
and theory to be in close agreement. In summer, however, the air-motion
was sufficient to give rise to appreciable disagreement. The disparity be-
tween fact and theory can be expressed as a simple empirical function of
wind-velocity. This then indicates approximately the extent to which
mixing reduces the electrode-effect at the Earth's surface.

Electric convection near the Earth's surface in fair weather. The tendency
of mixing to reduce the electrode-effect is equivalent, under normal circum-
stances, to the movement of negative charge toward the Earth. The electric
convection effected in this way constitutes a component of the electric cur-
rent between the atmosphere and the Earth. This convection-current is
directed oppositely to the electric conduction-current and, since this is

256 CARNEGIE INSTITUTION OF WASHINGTON

doubtless a worldwide feature, it is important to ascertain whether, as some
have claimed, it must be taken into account when considering the electrical
equilibrium of the Earth. However, the magnitude estimated by Gish, in a
study of the space-charge observations reported by Joseph G. Brown of
Stanford University, is not more than 1 per cent of the average electric con-
duction-current in fair weather at an altitude of 11 m from the surface at
that place. It is to be expected that in open country and at sea, where the
most representative measurements of the conduction-current are made, the
convection- current is even less than this estimate and can accordingly be
neglected when considering observations at such places.

Worldwide variations in atmospheric electricity. From observations made
at sea on cruises of the Carnegie it was first shown by S. J. Mauchly in 1921
that the diurnal variation in potential-gradient and that in the air-earth
conduction- current are aspects of a worldwide phenomenon in that the varia-
tions are everywhere in unison. This has since been found to apply over
land as well as at sea with certain exceptions which can be explained by local
causes. These and other worldwide variations of atmospheric-electric phe-
nomena are of interest because they are indirect manifestations of some
characteristics of that elusive fundamental element in atmospheric elec-
tricity which may be called the supply- current. The worldwide diurnal
variation in the conduction-current clearly indicates that the supply- current
for the whole Earth undergoes a diurnal variation. Does it also vary from
day to day or from year to year? The answer to that question may help to
ascertain the origin of the supply-current and hence also the origin of the
electric field and conduction-current in the atmosphere during fair weather.
It was reported last year that Wait and Mauchly found some evidence of a
tendency of the potential-gradient to vary in a similar manner from year to
year at three widely distributed places (Ebro Observatory in Spain, Huan-
cayo Magnetic Observatory in Peru, and Watheroo Magnetic Observatory
in Western Australia). This investigation was extended by Mauchly in
the summer of 1937 by taking into account the simultaneous variation of
the air-earth conduction-current. Although the results did not definitely
contradict those of the previous investigation, yet they indicated that be-
cause of numerous irregular variations more data must be examined before
definite conclusions are drawn. In the course of this investigation Mauchly
noted an apparent correlation between dates of radio "fade-outs" and dates
of high diurnal range in temperature. However, the effect, if real, is small
compared with the usual variations in the diurnal temperature-range from
other causes such as cloudiness and rain, and therefore considerably more
data must be examined by suitable statistical methods in order to test this
possibility.

GEOELECTRICITY

Lunar diurnal variation in earth- currents. The investigation of the lunar
diurnal variation in earth-currents, begun by Rooney during the last report-
year, was continued using the records from Tucson and Huancayo for the
year 1932. The monthly mean lunar diurnal variation was found to be quite
definitely semidiurnal in character and its amplitude was found to be less

DEPARTMENT OF TERRESTRIAL MAGNETISM 257

than one magnitude smaller than that of the solar diurnal variation. Har-
monic analyses show that the amplitude of the predominant second harmonic
is about one-sixth that of the solar diurnal variation at Huancayo and
about one-fifth that of the solar diurnal variation at Tucson. The form of
the mean curves is the same for both the equatorial station, Huancayo, and
the middle-latitude station, Tucson. In this respect they differ markedly
from the curves of solar diurnal variation.

The manner in which the lunar diurnal variation changes with the phase
of the Moon was also examined. Both components at Huancayo show a
marked increase in activity during daylight hours and a corresponding
diminution during the night, so that the curves constructed for a given phase
of the Moon are no longer of a simple semidiurnal character. These changes
are similar to those found in the corresponding curves for the magnetic ele-
ment. The Tucson data indicate that there is less difference between condi-
tions during day and night affecting lunar diurnal variation at this middle-
latitude station. Curves constructed for the individual phases of the Moon
at Tucson remained predominantly semidiurnal with only a slight decrease
in amplitude from day to night and comparatively small shifts in phase. It
would appear that variations in the ionization of the L-layer are most effec-
tive in producing earth-current variations near the equator. The Tucson
results are in good agreement with those obtained by Egedal and Rougerie,
using the data from Ebro and Pare St. Maur, Paris, respectively, both of
which are also middle-latitude stations.

Geoelectrical measurements in volcanological investigations. The ad-
visability of including electrical measurements in the proposed compre-
hensive program for volcanological investigations in Guatemala was con-
sidered by Gish and Rooney. They concluded that two aspects of such
measurements should be tried, namely, (a) a survey of earth-resistivity and
(b) registration of natural electrical potentials in the Earth in the vicinity
of the volcano. The resistivity-survey will doubtless yield an estimate of
the depth of volcanic ash or other overburden and may help to extend knowl-
edge of other hidden structure. The earth-potential measurements may
serve as an indicator of the activity of deep-seated volcanic processes. Rela-
tively large potential-differences between points on the Earth's surface are
observed in mountainous regions. There are reasons for thinking that these
arise from relatively deep-seated physical or chemical, or physico-chemical,
processes which may have geological significance (see annual report for
1936-37). Furthermore, Palmieri observed an apparent relation between
changes in such earth-potentials and the volcanic activity of Vesuvius.
These are the chief reasons for expecting to find variations in the earth-
potentials which correspond to changes in processes which are involved in
volcanism. Prediction of volcanic activity is a practical goal of volcano-
logical investigation. If the earth-potentials are associated with deep-
seated processes of volcanism, they may assist in such prediction. The
registrations which would serve this purpose could be made at a distance
from the volcano, that distance being limited only by the expense of install-
ing and maintaining a double-conductor cable or line similar to such as are
used for telegraph- or telephone-service.

258 CARNEGIE INSTITUTION OF WASHINGTON

INVESTIGATIONS OF THE IONOSPHERE AND ITS RELATION TO

TERRESTRIAL MAGNETISM

The origin of changes in the Earth's magnetism in the outer atmosphere
was conceived some 50 years ago in the theories of Stewart and Schuster.
They proposed that electrification of upper atmospheric regions would per-
mit conduction of electrical currents which produced these changes. Direct
experimental examination of the electrical state of the outer atmosphere was
delayed until the development by the Department of radio "sounding"
methods which permitted determination of the distribution of ionization
through the outer atmosphere. This type of investigation shows that a com-
plex structure of ionized regions or "layers" exists in this "ionosphere" of
the Earth. Because the ionization of this atmospheric region is produced
by sources external to the Earth, principally the ultraviolet light from the
Sun, the ionosphere forms a region of transition in which effects originating
on the Sun are translated into the geophysical effects observed on the Earth.
Exploration of the ionosphere is therefore fundamental to an understanding
of these geophysical, and in particular terrestrial-magnetic, effects which are
produced through this chain of events.

The productive field of investigation which was opened during the past
two years with the discovery that magnetic effects of the diurnal-variation
type are associated with certain bright chromospheric eruptions, and accom-
panying radio fade-outs in the sunlit hemisphere, was pursued vigorously
during the past year. Understanding of the underlying nature of the regular
daily changes of the Earth's magnetism which has come through this ap-
proach has proved most illuminating. The results represent a most impor-
tant advance in the science of terrestrial magnetism in recent years. It is
an interesting commentary that the broader inferences of these physical
effects are becoming apparent through collaboration of workers in diverse
fields of physics who observe them in their different aspects.

The ionospheric investigations reported last year demonstrated that the
radio fade-out — the sudden failure of high-frequency radio-wave transmis-
sion in the sunlit hemisphere, which coincides with certain bright chromo-
spheric eruptions — must be due to the absorption of the radio waves in the
lower ionosphere. It appeared that this was due to intense production of
ions in the region between about 60 and 100 km above the Earth. The
coincident magnetic effect was then explained as occurring because of an in-
crease in electric current-flow in this region of increased electrical conduc-
tivity. Because the magnetic change was an augmentation of the diurnal
variation of the Earth's magnetism, it was possible to deduce, from a detailed
investigation of certain seeming anomalies, that this was also the region
in which flowed the electrical currents which produce the magnetic diurnal
variation.

Continuation of the ionospheric investigations by more exact and exhaus-
tive methods has confirmed these views, and has narrowed the range of
heights in which these current-sheets must be principally confined. Using
the automatic multifrequency technique, it has been demonstrated that the
radio fade-out effect occurs because of intense ionization produced below the

DEPARTMENT OF TERRESTRIAL MAGNETISM 259

level of the Z£-region of the ionosphere by the ultraviolet light emitted from
hot gases of the bright chromospheric eruption. Thus the more intense effects
occur below a height of about 90 km. The upper regions of the ionosphere
are unaffected by the passage of this ultraviolet light through them, experi-
mentally demonstrating that the ionized regions must be produced by proc-
esses of selective absorption. The quantitative evidence thus obtained has
stimulated further investigation of the physical properties of the outer
atmosphere and of the processes of absorption and ionization involved in the
production of the various ionized regions.

Beginning of continuous operation of the automatic multifrequency equip-
ment for investigation of the ionosphere at the Huancayo and Watheroo
magnetic observatories of this Department has been an important step in
the advance of ionosphere-research. This equipment gives a continual record
of the distribution of ionization through the whole of the ionosphere so far
as it is possible to obtain it by radio sounding methods. The records permit
investigation of the relation of ionospheric effects to solar and geophysical
phenomena of which the investigation of radio fade-outs cited above is but
one example. These records are disclosing new physical effects in the outer
atmosphere hitherto unsuspected from earlier data obtained by cruder
methods.

Investigations were instituted to determine the relation of the several
regions of the ionosphere to magnetic disturbances or "storms." That the
ionosphere must be related to magnetic effects of this sort is indicated both
by theory and by the marked changes in long-distance radio-wave propaga-
tion coinciding with magnetic disturbances. The relation is not a simple
one, for the nature of ionospheric fluctuations which occur at the time of
magnetic disturbances changes with time of day and with season. While
some of these features are apparent, it appears that a statistical treatment
of the data will prove most fruitful in comprehensive examination of the
relation. Heretofore lack of continual observation has hampered investiga-
tion of such effects but the introduction of the automatic multifrequency
methods makes available a wealth of material for quantitative treatment.

A curious anomaly is found in the investigation of the maximum ion-den-
sity of the highest (F2-) region. Simple theory of ionization by ultraviolet
light from the Sun predicts that ion-density should change with altitude of
the Sun, and should be therefore a simple function of declination, latitude,
and hour-angle of the observing station. This simple type of variation is
observed for the normal maximum ion-densities of the lower (E- and Ft~)
regions. To explain the more complex changes of maximum ion-density of
the upper (F2-) region, the concept of heating with consequent expansion of
the outer atmosphere at small zenith-angles was introduced. This extended
theory offered an explanation for the increased virtual heights of the F2-
region which are observed in summer, but failed quantitatively to predict
the variation of maximum ion-density for a station in one hemisphere from
that in the other. A detailed analysis of the data obtained at Watheroo in
the Southern Hemisphere and at Washington in the Northern Hemisphere
shows that a further factor must be added empirically to the theory which
accounts for a variation-component of maximum ion-density which occurs

260 CARNEGIE INSTITUTION OF WASHINGTON

at both stations in the same phase. This component has a period of one
year, but it is not a seasonal component in the sense that such a component
should differ in phase by six months in the Northern and in the Southern
hemispheres. On the contrary, this non-seasonal or annual component
reaches a maximum about January and a minimum about July at both sta-
tions. The origin of this variation-term is not yet known.

Extended analysis of the data also brings out the marked change of ion-
density of the ionosphere with change of solar activity. Annual average
maximum ion-density of the jF2-region at noon has been linearly related to
annual average sunspot-number during the rise of the present cycle of solar
activity. Other regions are undergoing similar changes. Because the ioniz-
ing radiation is absorbed in the outer atmosphere, and cannot be seen from
the Earth's surface, these investigations are extending our knowledge of solar
radiation into the far ultraviolet spectrum — the more exactly as our knowl-
edge of selective absorption-processes in the outer atmosphere increases.
These far ultraviolet radiations are much more variable than the visible
radiation, which is sensibly constant, and, being intimately associated with
other little-understood solar variations, give a new approach to solar physi-
cal problems.

A most interesting development during the past year was the evaluation
of the Lorentz polarization-correction in the ionosphere. The relation be-
tween the constitution of a conducting medium and its refractive index is a
fundamental problem of classical physics to which attention has been devoted
for many years but which even now is not completely solved. The question
at issue is whether the force per unit-charge exerted by an electric field upon
an elementary charged particle in the medium should be taken simply as

the Maxwellian electric intensity E (the Sellmeyer theory) , or whether there

should be added a contribution (4jt/3)P (the Lorentz theory), P being the
electric moment per unit-volume produced by the electric field in the neigh-
borhood of the charged particle under consideration. For conduction of elec-
trons in metals under the influence of steady and alternating electric fields
ordinarily encountered, the Sellmeyer theory is universally taken for granted.
There was some question, however, as to whether the Sellmeyer or Lorentz
theory was applicable in the ionosphere, and this led to an extended theoreti-
cal discussion of the point. An experiment for deciding between the two
theories depends upon reflection from the ionosphere of radio waves of fre-
quency less than the gyromagnetic frequency. There is in middle latitudes
a clear-cut distinction in the behavior of the extraordinary wave according
to the two theories. Over the past year a large number of records showing
magneto-ionic splitting of ionospheric echoes at these wave-frequencies was
obtained at the Kensington Experimental Station of the Department using
the automatic multifrequency equipment which for the first time has per-
mitted such detailed observations. It appears impossible to interpret these
observations in terms of the Sellmeyer theory but no objection exists to their
interpretation in terms of the Lorentz theory. It appears therefore that it is
the Lorentz theory which must be used in the ionosphere at wave-frequencies
employed in ordinary broadcasting.

DEPARTMENT OF TERRESTRIAL MAGNETISM 261

The program of ionospheric investigation was carried on by Berkner at
Washington, by Stanton and Wells at Huancayo, and by Seaton and Hogan
at the Watheroo Magnetic Observatory until April 1938, when the latter
were joined by Berkner. With the installation of the automatic multi-
frequency apparatus, the ionospheric program at the observatories was made
a part of the regular schedule, with all observers taking part in maintenance
of the program and in the reduction of the records obtained. The Department
was fortunate to have also the services of Dr. H. G. Booker of Christ's Col-
lege, Cambridge, England, as guest from September 15, 1937, during his
sabbatical year's leave from Cambridge University.

RESULTS

Recording of data. The introduction of the automatic multifrequency re-
cording equipments at the Huancayo and the Watheroo magnetic observa-
tories represents the culmination of several years of research, development,
and construction of a type of equipment capable of delineating the ion-
distribution of the ionosphere as completely and continuously as possible
at stations in the field. With this equipment successive observations of vir-
tual height are made automatically at exceedingly small increments of wave-
frequency change over the range of 0.516 to 16.0 mc/sec by determining the
echo-time at each frequency. Each sweep through this frequency-range
occupies 15 minutes, four sweeps being made each hour. In manner the
virtual height of each ion-density through the range of ion-densities en-
countered in the ionosphere is measured, the ion-density required for reflec-
tion of the wave being proportional to the square of the wave-frequency of
each transmitted pulse. From the curves thus formed on the photographic
trace, the critical frequency of penetration, minimum virtual height, and
other characteristics of each region are determined. Each record has a base-
line which consists of thousands of pulses of about 100 microseconds' duration
transmitted on wave-frequencies beginning at 16.0 mc/sec and spaced at
small increments of frequency down to 0.516 mc/sec. The reflections from
each transmitted pulse are recorded along the vertical scale, which is ap-
propriately calibrated in virtual height as determined from the time for the
pulse of waves to travel to the reflecting stratum and return. Because suc-
cessive reflections from a given region form a coherent trace on the record,
the resultant curves appear continuous as contrasted with the incoherent
spots of interference and noise which are scattered on the trace in a random
manner and therefore appear only as a slight fogging on the record. Care
has been taken to adjust the character of the emission so that no interfer-
ence to other radio services, through whose transmission-channels the emis-
sion must pass, would occur. The equipment has met with the full approval
of the American, Peruvian, and Australian authorities in this respect.

Ninety-six of these records are obtained each day, and from them can be
formed in three dimensions the picture of ion-distribution of the ionosphere
in terms of ion-density with respect to height and time. Continuous record-
ing of this nature was begun at the Huancayo Magnetic Observatory in No-
vember 1937, and at the Watheroo Magnetic Observatory in May 1938.
Prior to these dates, more restricted measurements using the manual multi-

262 CARNEGIE INSTITUTION" OF WASHINGTON

frequency technique together with fixed-frequency recording were made on
regular schedule as described in previous reports. During the development
of the equipment in the past year, an extended series of records was also
obtained at the Kensington Experimental Station of the Department.

Analysis of the radio fade-out effect. Multi frequency observation confirms
and extends the conclusions already drawn as to the nature of the radio
fade-out effect from the fixed-frequency data reported last year. The dura-
tion of the fade-out as observed at normal incidence is an inverse function
of the frequency of measurement. The commencement is not quite imme-
diate on all frequencies, so that the time of commencement may appear
slightly different to different observers, depending upon the transmitter-
frequency, power, and location with respect to the subsolar point. The
investigations indicate that no significant change occurs either in the virtual
height or the maximum ion-density of the Fx- or jP2-i"egions during the fade-
out. When the time required for establishment of equilibrium-conditions is
considered for the several regions it appears most probable that no change
in the Ft or i^-regions has occurred. A small increase in the ion-density
and virtual height of the £J-region which appears significant is observed.
This is sufficient to account for the destruction of the normal £7-region reflec-
tion-boundary previously described. Abnormal absorption of the wave con-
tinues after ^-region conditions return to normal, confirming the view that
absorption must occur below the level of maximum E'-region ionization. It
seems probable, therefore, that the intense ionization causing the fade-out
occurs predominantly below the 100-km level, and probably below 90 km,
the effect extending up into the E-region only slightly. The absorption of
the ionizing radiation from the Sun which produces the fade-out must be
negligibly small in the Ft and i^-regions to account for the stability of
these regions during the fade-out. The radio fade-out can now be defined
by the sudden extension upward in wave-frequency of the low-frequency
absorption-limit which is determined by the lowest frequency on which reflec-
tions can be observed. This is ordinarily in the frequency-range of the radio-
broadcast band. During intense fade-outs this low-frequency absorption-
limit is projected through the entire frequency-range in which reflections can
ordinarily be observed, thus blotting out all propagation from the upper
regions of the ionosphere.

Ionospheric disturbances. Records obtained by the automatic multifre-
quency technique during magnetic disturbances indicate that in middle lati-
tudes at night the maximum ion-density of the F-region is consistently de-
creased during disturbed periods. Accompanying this decrease is a great
increase in the scattering of the wave, the reflections no longer coming from
a well-defined height. Furthermore, the minimum virtual height is increased
greatly and the reflection-intensity is noticeably diminished, multiple reflec-
tions often entirely disappearing during the more pronounced disturbances.
This indicates a change from the normal well-defined layer-structure of the
F-region to a diffuse region with a considerable inhomogeneity in density.

During daylight hours a slight decrease in ion-density of E- and /^-regions
is observed as reported previously. Effects in the F2-region vary with sea-
son. In summer in middle latitudes the ion-density of this region decreases

DEPARTMENT OF TERRESTRIAL MAGNETISM 263

violently during more marked disturbances, often falling to a value less than
the maximum ion-density of the iVregion so that the F2-region may be
invisible behind it for some hours at a time. The effect is accompanied by
a marked increase in virtual height. During a winter day, however, the
ion-density tends to increase slightly at the onset of the disturbance, later
decreasing markedly for the more pronounced disturbances.

Commencement of automatic multifrequency recording at Huancayo has
been so recent that detailed analysis of these records for magnetic effects
has not yet been possible. Perusal of these records, however, indicates that
conditions observed in middle latitudes are modified in equatorial regions in
several important respects. The study is not sufficiently advanced, there-
fore, to permit generalizations, but rather to indicate the most profitable di-
rection of the investigation.

In addition to the effects associated with magnetic disturbances, there
occur at times violent increases or decreases in ion-density of the F2-region
lasting over a period of a day or more, which do not appear to be connected
with a particular magnetic disturbance. These might be considered as
"ionospheric storms" of a special type.

Analysis of fluctuations of F2-region ion-densities. Observation of F2-re-
gion ion-density in the Northern and Southern hemispheres indicates that
variations of maximum ion-density are inconsistent with the hypotheses
which have been advanced to explain them. In order to determine the
quantitative nature of the discrepancy, the data from the Watheroo Magnetic
Observatory and from the National Bureau of Standards at Washington have
been analyzed. It has been reported previously that observed variations
at Watheroo and at Washington were not simply reversed in phase as ex-
pected from calculation of supposed seasonal effects. On the contrary, it
appeared that a variation-component of large amplitude and of period of
approximately one year occurred in the same phase at both stations. In
the recent analysis, a simple method is used to separate the variations having
opposing phase in the two hemispheres from the background appearing at
both stations. Over the three-year interval analyzed from 1935 to 1937, a
large variation-component exists which is in the same phase at both sta-
tions. This has a principal period of one year and an amplitude approxi-
mately equal to the amplitude of the component of variation which is in
opposite phase at the two stations. It is not a seasonal variation in the sense
that such a seasonal variation must be the same function of local zenith-
angle in the two hemispheres and, therefore, should have a phase which differs
in the two hemispheres by six months. The maximum amplitude of this term
appears in January and the minimum in July at both stations simultaneously.
The fact that the in-phase variation-component has a period of one year
strongly suggests that it is related to the Earth or its motion. Less critical
examination of the data from five other stations in both hemispheres indi-
cates a dip in maximum noon ion-density of the /^-region in July at each
station, suggesting that the effect is a general one. It therefore appears
necessary to add empirically a correction-term to existing theories which
accounts for this in-phase fluctuation if they are to predict the ion-density
in any location.

264 CARNEGIE INSTITUTION OF WASHINGTON

It is found that the rise in annual averages of noon ion-density has an
almost perfect correlation with annual average sunspot-numbers over the
three-year period during the present rise in solar activity. This can be
expressed quite closely by the expression

*N = (3.7 + l.l^)105\/cos~7
where the Lorentz polarization-correction is assumed as zero. There ap-
pears to be no correlation, however, between deviations of the in-phase fluc-
tuations of ion-density from the curve through annual means and corre-
sponding short-time fluctuations of sunspot-number. Therefore the in-phase
variation-component cannot be readily explained by resort to sunspot-
changes.

The Lorentz polarization-correction. Experimental determination of the
Lorentz polarization-correction is an excellent example of the use of the
ionosphere as a low-pressure region unbounded by sidewalls for the conduct
of physical experiments. The experiment was made) possible by the ad-
vanced experimental technique of the Department described above. The
experiment depends on the fact that, for radio waves, the ionosphere is
rendered doubly refracting by the influence of the Earth's magnetic field.
Free electrons in the ionosphere gyrate around the Earth's magnetic field
with a frequency in the order of a megacycle per second. For wave-fre-
quencies less than the gyromagnetic frequency there is, under suitable condi-
tions, a clear-cut distinction in the behavior of the extraordinary wave ac-
cording to the Sellmeyer and to the Lorentz theory. The distinction becomes
apparent when measuring the variation of echo-retardation with frequency
below the gyromagnetic frequency in certain regions of the Earth. Where
the magnetic dip is greater than 35° but less than the value at which vertical
propagation in the ionosphere at wave-frequencies under consideration
passes from quasi-transverse to quasi-longitudinal type, the distinction be-
tween the two theories is the following. According to the Sellmeyer theory,
the virtual height of the extraordinary wave increases to infinity as the
wave-frequency increases to the gyromagnetic frequency. However, on ac-
count of strong absorption of this wave-component in the immediate neigh-
borhood of the gyromagnetic frequency, it would be impossible to trace the
extraordinary wave to an enormous virtual height at a wave-frequency just
below the gyromagnetic frequency. On the other hand, according to the
Lorentz theory, the virtual height of the extraordinary wave increases to
infinity as the wave- frequency increases to a value known as the Lorentz
frequency and which is definitely below the gyromagnetic frequency. More-
over, the absorption of the extraordinary wave just below the Lorentz fre-
quency according to the Lorentz theory is less than it is just below the
gyromagnetic frequency according to the Sellmeyer theory.

At the Kensington Experimental Station, where the magnetic dip is be-
tween 71° and 72°, the Lorentz frequency, neglecting the effect of heavy
ions, is about 17 per cent less than the gyromagnetic frequency. Moreover,
the reflection-coefficient of the extraordinary wave just below the gyromag-
netic frequency according to the Sellmeyer theory is about four orders of
magnitude less than it is just below thq Lorentz frequency according to the
Lorentz theory. The ionospheric records obtained at this station show

DEPARTMENT OF TERRESTRIAL MAGNETISM 265

echoes which tend to infinity as the wave-frequency increases to 1.38 mc/sec.
At a frequency slightly below 1.38 mc/sec it is actually possible to recognize
the individuality of successive echoes, the wave-frequencies of which differ
by known amounts, and to deduce that the virtual height is here increasing
with increase of wave-frequency at about 100 km per kilocycle per second.
These echoes can be traced to enormous retardations corresponding to virtual
heights exceeding 1600 km per second. It appears from this immediately
that return of echoes from such great heights as the retardation tends to
infinity is incompatible with the large absorption expected on the basis of
the Sellmeyer theory. Furthermore, the value of the gyromagnetic fre-
quency at Kensington is 1.61 mc/sec, and if it decreases with increase in
height according to the inverse cube of the distance from the Earth, it has a
value of 1.54 mc/sec at a height of 100 km and 1.44 mc/sec at 250 km. The
records show that prominent among the multiple echoes of this reflection are
echoes which, in addition to having traveled up to the F-region and back
again, have been reflected back and forth between the E- and F-regions one
or more times, suffering partial reflection from the top of the ^-region. The
consequent additional retardation suffered by these multiple echoes is almost
independent of wave-frequency. This confirms the theoretical expectation
that the large retardation experienced by the echoes just below 1.38 mc/sec
takes place in the lower part of the i£-region, where it can be shown by both
theory and experiment that the gyromagnetic frequency must be greater
than 1.5 mc/sec. The interpretation of these observations in terms of the
Sellmeyer theory therefore seems impossible. The observations can, how-
ever, be explained in terms of the Lorentz theory. To obtain a good quan-
titative interpretation, it is necessary to realize that good theoretical reasons
exist for believing that considerable numbers of molecular ions exist in the
lower part of the ^/-region, and that these somewhat affect the value of the
Lorentz frequency. This concept is a powerful tool in determination of
molecular-ion concentrations in the lower ionosphere. The ratio of molecular
ion-density to electron-density in the lower part of the E-region turns out
to be about 10,000. Heavy ion-concentrations of this magnitude are re-
quired to explain satisfactorily the diurnal variation in terrestrial magnetism.

COOPERATIVE ENDEAVOR

The Department cooperated with Dr. C. T. Kwei of the Central China
College, Wuchang, in investigatory work on the ionosphere. In the fall
of 1937, a manually operated ionospheric equipment, as designed at the
Department according to a scheme proposed by T. R. Gilliland of the
National Bureau of Standards, was installed in the Physics Department
of the Central China College, at Wuchang (latitude 30° 34' north, longitude
114° 21' east). With this apparatus a single operator can make necessary
readings of the virtual heights and critical frequencies. From data for
noon-hour runs from October 1937 to January 1938 and from April to June
1938, and half -hour evening runs in March and April 1938, it is found
that the critical frequencies at Wuchang are higher than those at Wash-
ington for both the E- and jP2-layers during the same months. The E-layer
critical frequency, as observed also in other places, reaches a maximum

266 CARNEGIE INSTITUTION OF WASHINGTON

near local noon, whereas, for the i*Vlayer, the critical frequency attains
a high value about 14h, maintaining nearly the same level until about 17h,
120° east meridian time. When plotted month by month, the ^-region
critical frequency increases with the approach of summer while the F2-layer
critical frequency has a tendency toward a minimum in July with two
probable maxima in October and April. This seems to indicate that the
seasonal characteristics at Wuchang approximate those of Watheroo rather
than those of Washington, but the data available are not sufficient to verify
this point. Very frequently the virtual height of the 2?-layer undergoes a
dip on the appearance of a higher layer and continues to keep its normal
height long after the upper layer has appeared. In a few cases, the E-l&yer
echoes persist even after the penetration of the F- and i^-layers. Magnetic
splitting is quite evident especially in the day readings. The observed mean
value of 620 kc as the difference between the ordinary and extraordinary
components of the F2-layer penetrating frequency agrees well with the
theoretical value of 614 kc.

Close contact must be maintained by the Department with other inves-
tigators in this field because of the worldwide aspects of the problem. In
order that the data may be most widely disseminated, arrangements have
been made for quarterly publication of the ionospheric information obtained
at the observatories in the Journal of Terrestrial Magnetism and Atmos-
pheric Electricity, and the data are prepared with this end in view. The
Department also maintains cooperation with other workers, that the more
important information obtained elsewhere may be available also for study.

The fourth annual Conference on Ionospheric Investigations was held at
the Department on April 30, 1938. It was attended by forty investigators
from the Bell Laboratories, the Radio Corporation of America, the National
Bureau of Standards, the Department, and numerous universities and other
organizations. Subjects discussed were: transmission-conditions and mag-
netic activity; variations in transmission-conditions; radio transmission in
the troposphere and stratosphere; Lorentz correction for polarization; de-
velopments in methods of investigation ; and absorption of solar radiation in
the ionosphere. Considerable interest centered about the relation between
radio transmission and magnetic activity. Recognition was given the service
of the Department in compiling regular bulletins of the American magnetic
character-figure and supplying them to interested investigators.

While en route to the Watheroo Magnetic Observatory, Berkner visited the
Cavendish Laboratory at Cambridge and the Imperial College of Science and
Technology at London to confer with Professors Chapman and Appleton, and
others actively engaged in various phases of ionospheric research.

Among distinguished visitors at the Department during the year to study
methods of and equipment for ionospheric research were Dr. A. R. Hogg of
the Commonwealth Solar Observatory of Australia, W. C. Gee of the Feder-
ated Malay States Posts and Telegraph Department, Dr. Yoji Ito of the
Naval Reserve Laboratory of Japan, and Professor G. W. Kenrick of the
University of Puerto Rico. Upon request complete sets of blueprints showing
design and construction of the multifrequency ionospheric recording equip-
ment were supplied Professor E. V. Appleton of Cavendish. Laboratory, Cam-

DEPARTMENT OF TERRESTRIAL MAGNETISM 267

bridge, England, Dr. Yoji Ito of the Naval Research Laboratory, Tokyo,
Japan, and Professor M. N. Saha of the University of Allahabad, India.

INSTRUMENTAL DEVELOPMENT

A further investigation of antenna-design for most suitable use in connec-
tion with the automatic multifrequency equipment was conducted theoreti-
cally and checked experimentally at the Kensington Experimental Station.
This dealt principally with adjustment of length and height to values such
as would least affect the radiation-pattern in the upward direction with
changing Earth conditions and would maintain the most uniform upward
radiation over the whole range of wave-frequencies. The antenna-structure
finally designed maintains upward radiation sensibly uniform at all fre-
quencies for constant power-input, and is little affected by changing ground-
conditions.

The development of a suitable constant-frequency controller capable of
holding the speed of a one-kilowatt alternating-current generator to a high
degree of precision was completed at the Watheroo Magnetic Observatory.
Inasmuch as the standards of virtual height and wave-frequency along the
ionospheric records depend upon the speed of rotation of the associated
synchronous driving mechanisms, especially good frequency-control of the
generating equipment is necessary. The present controller is capable of main-
taining constant speed to about one part in 50,000 when operated from a
temperature-controlled tuning-fork. The speed of the generator is maintained
constant by means of a gas-discharge tube controlled from the tuning-fork,
with associated circuits to prevent phase-changes with the wide range of
input-voltages experienced in the field.

Kensington Experimental Station. Operation was continued at the Ken-
sington Experimental Station of the Department near Kensington, Maryland,
involving principally development and test. This station operates under the
special and general experiment radio licenses W3XI and W3XFE. Con-
tinued occupancy of this station was possible through the courtesy of Colonel
M. K. Barroll, U. S. A. (retired), who maintains an active interest in this
work.

MAGNETISM AND ATOMIC PHYSICS
FORCES AND INTERACTIONS GOVERNING THE PRIMARY PARTICLES OF MATTER

Magnetic movement and angular spin have been found, perhaps somewhat
unexpectedly, to be among the very few properties or attributes intrinsically
possessed by the smallest particles of matter, as distinguished from those
properties which arise when numerous particles interact with each other.
Experiments in the laboratory designed for the study of the interactions of
the primary particles of matter under the least complex conditions, for ex-
ample, the collision of a single proton with another single proton or single
neutron (a proton is the positively charged nucleus of a hydrogen atom, and a
neutron is a similar particle having zero electrical charge), accordingly have
been the principal feature of the Department's program on fundamental
physics in relation to magnetism during the past decade.

There are several other broad problems open to experimental attack for

268 CARNEGIE INSTITUTION OF WASHINGTON

which an excellent case can be made as relating perhaps more immediately
to the specific field of terrestrial magnetism. The radio-echo method for study
of the upper atmosphere, contributed in 1925 by the Department and now
such a fruitful part of the observatory-program on terrestrial magnetism
throughout the world, is a historical illustration of the point. The discovery
of the radio echoes and the demonstration of the powerfully analytical virtues
of this method for upper-air investigation stand as a fundamental contribu-
tion by the Department to the field of geophysics. Today one may predict,
for example, that further study in the laboratory of the properties of matter
under exceedingly high pressures, utilizing the cascade-principle to extend
the limits of previous work, offers an opportunity for important contribution
to basic physical knowledge, having also direct relation to the Earth's mag-
netic properties. Suggestions for novel apparatus and a new attack in this
direction in fact developed in the Department's laboratory during 1936 ; this
and the modulated-searchlight method for upper-air studies (see previous
reports) are typical of the possible experiments which would emphasize the
approach through the laboratory, as contrasted to that through the observa-
tory, toward the general field of Earth physics.

One cannot ask for a more fruitful and far-reaching result, however, than
the achieved first direct experimental determination of the enormous attrac-
tive forces at short distances which are exhibited by the heavy building-blocks
of matter — protons and neutrons — which has resulted from concentrating
efforts on the "simplest" kinds of problems which can be formulated regarding
the primary particles of matter. Since initiating the Department's program
the subject has even acquired a distinct name of its own: nuclear physics.
The attractive forces between the primary particles are called nuclear forces,
being responsible for the aggregation of groups of protons and neutrons to
form the nuclei of all atoms of the chemical elements.

Following years of technical development toward this announced objective,
the first measurements on these proton-proton and proton-neutron forces are
described in the reports for the past two years. During this report-year
further detailed observations were made, giving measurements entirely inde-
pendent of the earlier series and — a point of particular importance — cali-
brated in terms of absolute units (centimeters, grams, seconds). The reduc-
tion to an absolute scale, done indirectly in the previous work, vitally affects
the exact significance of the measurements. It was done by measurements
on the collisions of high-speed protons with helium, nitrogen, oxygen, and
argon nuclei, using the same apparatus and technique as for the observations
on proton-proton collisions which give a measure of the proton-proton forces.
Details of these observations are given in the published technical papers.

THE ATOMIC-PHYSICS OBSERVATORY

The construction of a high-voltage equipment for nuclear physics, hav-
ing adequate range and characteristics for a comprehensive program of
precision measurements, was the chief feature of the work during this
report-year. Despite the demands of this work on the staff, it was possible
by careful planning and administrative support to keep both target-positions
of the existing one-million-volt equipment in full operation daily on the

DEPARTMENT OF TERRESTRIAL MAGNETISM 269

two main scientific problems described in the paragraphs above and below.
As the report-year closes the summer humidity has stopped these observa-
tions (the new equipment has humidity-control) and all members of the
staff are pushing the new equipment toward its first high-voltage tests.

The new equipment comprises a constant-potential (electrostatic) gener-
ator and vacuum-tube designed to reach potentials in excess of five million
volts under precise control. Insulation is by dry air compressed to 50
pounds per square inch in a pear-shaped steel tank 55 feet high and 37.5 feet
in diameter, and adequate provision is made for shielding observers and
instruments (against penetrating radiations) and for auxiliary equipment.
Similar equipments are being constructed at the Westinghouse Research Lab-
oratory and the University of Minnesota under the direction of former mem-
bers of the Department's staff and based directly on the designs and technique
developed here; other units are being planned elsewhere.

A technical problem of considerable interest which was met and solved
in the construction of the new equipment was that of the mechanical
stability of the high-voltage unit. This consists chiefly of a 12,000-pound
steel ball (19 feet in diameter) supported 26 feet above the grounded base
(inside the steel tank) on four porcelain pillars, six feet on centers. The
unreliable mechanical properties of porcelain under any type of stress
except compression are well known. Bending moments in these tall sup-
porting columns, arising from motions of the base (outer tank) due to
winds, and motions of the high-voltage ball itself due to main belts and
machinery, had to be taken care of without allowing tension or excessive
shear in the porcelain. The requirement was met by providing a succession
of stiff steel platforms intermediate between the base and the high-voltage
ball. The porcelain supports are then in the form of short columns of
small slenderness ratio between successive platforms. Rubber pads at
each end of each porcelain, and at the four base-corners, permit the system
to take up several hundred foot-pounds of energy without excessive stresses
on the porcelains or elsewhere. Tests on the completed mechanical struc-
ture have verified its calculated stability and limits of safety. The coopera-
tion of the National Bureau of Standards in the tests for wind-motions
of the large steel tank and in loan of surplus porcelain insulators for con-
struction of the support columns is gratefully acknowledged. Certain
features of the new equipment are designed with reference to its use for
producing X-rays at very high voltages; some of the measurements on
these are planned in cooperation with the National Bureau of Standards
investigators as an extension of its present X-ray measurements.

NUCLEAR STRUCTURE— A NEW ISOTOPE OF BERYLLIUM

The actual laws governing the behavior of the strong attractive forces
between the primary particles of matter in forming atomic nuclei have
not yet been established. This is the problem of nuclear structure, and
it appears to be inherently a many-body problem, in contrast to the problem
presented by the outer (electronic) structure of the atom. The latter has
been successfully treated in terms essentially of the separate motion of
each particle, as influenced by the average field due to the rest of the

270 CARNEGIE INSTITUTION OF WASHINGTON

particles. Because of the extremely small size of an atomic nucleus
(10~12 cm), and the comparable range of the intense nuclear forces, each
particle in a nucleus, however, appears to be at all times strongly influenced
by every other particle. This means that a detailed description of nuclear
dynamics is well-nigh humanly impossible, except for the simplest cases
of nuclei composed only of two or three particles. In view of this situation
a considerable part of the available time has been spent during the past
several years on detailed and quantitative measurements of all nuclear
processes involving the two lithium isotopes, which are comprised of six
and seven primary particles, respectively, in order to obtain as extensive
information as possible regarding the simplest examples, so to speak, of
the complex nuclear structures of all heavier chemical elements.

The discovery in the Department's laboratory during this report-year
of a hitherto unknown isotope of beryllium of mass seven is an illustration
of the type of information sought in these studies. This, isotope, Be7, has
been demonstrated to occur as a product in several reactions of lithium
and boron; it is a radioactive isotope with a half-life of about 43 days
which reverts to Li7, the normally stable nucleus of mass seven. The radio-
activity in this case is unusual, however. The experiments have shown
that the normal (unexcited) configuration of Be7 has such a low energy
that radioactivity cannot occur in the usual way by the expulsion of an
electron (positron) from the nucleus; there is not sufficient potential-energy
available to create the rest-mass of the electron. The transition to Li7
hence can only occur by the capture of an external (negative) electron,
usually no doubt from the K-shell of the parent atom. "Silent radioactivity"
of this kind is known for a few heavier chemical elements, but the case
of Be7 is of special quantitative interest for two reasons. K-electron
capture should be a distinctly rare event with a nuclear charge as low
as four (beryllium) and, second, the capture in this case can occur in
either of two ways: by the emission of a high-energy neutrino (about 1
mev), leaving the resultant Li7 in the normal state, or by the emission of
a medium-energy neutrino (about 0.5 mev), leaving the Li7 in its 440-kv
excited state; it then subsequently reverts to the normal state by the
emission of a gamma ray. Measurements of these gamma rays have thus
given experimental information concerning the relative probability of emis-
sion of neutrinos of different energies. This question has hitherto not been
experimentally accessible. The basic importance of the so-called neutrino
problem — another name for the apparent lack of conservation of energy
in those nuclear processes which involve loss or capture of electrons —
makes the data of these experiments particularly welcome.

THEORETICAL-PHYSICS CONFERENCE

A fourth "Washington Conference on Theoretical Physics" was held March
21 to 23, 1938, under the joint auspices of the George Washington University
and of the Institution, acting through this Department. The subject of
nuclear physics has developed so rapidly during the past few years that
laboratory-data are now available with regard to nearly all the nuclear
reactions which might conceivably serve as sources of energy for the stars.

DEPARTMENT OF TERRESTRIAL MAGNETISM 271

That the great lifetimes of the Sun and the stars, pouring out inconceivably
vast amounts of radiant energy each second of their existence, must be
ascribed in some way to actions of the nuclear forces seems evident. The
subject of this year's Conference was "The problem of stellar energy," and
eleven investigators in astronomy, astrophysics, and theoretical and experi-
mental nuclear physics were brought together for three intensive days of
technical and informal discussion. About twenty visitors also attended the
various sessions. The purpose of this Conference was to examine the extent
to which definite conclusions could already be drawn or limits set regarding
the mechanism of the energy-supply inside a star, primarily with a view
toward guiding the next immediate efforts of investigators in the various fields
relating to this important problem. Resonance processes and highly con-
densed "star-nuclei" were among the important technical features under
discussion. The Conference produced gratifyingly definite results in three
directions. Several tentative theoretical proposals regarding the mechanism
of stellar energy-supply were ruled out very definitely on the basis of the
measurements in the laboratory during recent years on nuclear processes.
In addition, it was shown numerically that none of the ordinary nuclear
processes satisfies the stellar requirements, limiting the search to two or three
rare but possible reactions not as yet established in the laboratory. A third
result, subsequent to the meeting here, was the suggestion of a reaction-chain
involving carbon by one of the members of the Conference, which appears
to fulfill in large measure the requirements set. Quantitative investigation
of the several definite questions, both theoretical and experimental, which
were raised during this Conference is already resulting in accelerated progress
on the problems of stellar energy.

MISCELLANEOUS

Experiments and other activities not directly a part of the current program,
aimed at two or three fundamental objectives, have been kept at a minimum
during the report-year, since about half of the available time has had to be
spent on the new high-voltage equipment under construction. As soon as this
new equipment is in operation, experimental data on these supplementary,
but often very important, problems can be successfully obtained with much
less expenditure of time and effort than is required with the present one-
million-volt installation. Some preliminary observations using radioactive
sulphur and one or two other radioactive "tracers" in chemical studies have
been made. Applications of this technique to certain fundamental problems
in biology are planned in cooperation with investigators outside the Depart-
ment. Mutation-studies, using gamma rays and neutrons, in cooperation
with the Institution's Department of Genetics, were interrupted, to be re-
sumed on completion of the new equipment. Observations on the background
light of the night sky verified the earlier indirect estimates and made it clear
that no serious difficulties are to be expected in the use of the modulated-
searchlight method for study of the upper air. A few observations on the
searchlight beam at low altitudes showed the necessity for a steady and
accurately oriented field-mounting for the receiving mirror. The beam is

272 CARNEGIE INSTITUTION OF WASHINGTON

invisible at great heights, and the setting of the receiver must be made
entirely by instrument.

Several hundred technical and scientific visitors gave our work detailed
personal inspection during the past year. As most of these men are engaged
in or are beginning researches similar to our own, their visits and questions
are welcome, but record should perhaps be made of this more or less incidental
contribution by the Department's laboratory to scientific progress.

The staff during the year included Hafstad, Heydenburg, Meyer, Roberts
(Carnegie Institution Fellow), Rumbaugh (guest-investigator to September
1, 1937), Schmidt (laboratory apprentice), and Tuve. Professors Breit
(University of Wisconsin) and Gamow (George Washington University), as
research associates, gave much valuable assistance, as also Professor Teller
of George Washington University.

PUBLICATIONS

Publications relating to the above investigations are noted in the bibli-
ography below.

Formal talks were presented as follows : Washington Physics Colloquium,
November 24, 1937, by Hafstad on "Progress-report on the new high-voltage
equipment" and December 8, 1937, by Hafstad on "The neutron reactions of
lithium"; Study Club of Washington Dentists, December 6, 1937, by Hafstad
on "The Atomic-Physics Observatory"; Pittsburgh Physics Colloquium,
February 3, 1938, by Hafstad on "Proton-proton scattering"; General Elec-
tric Research Laboratory Colloquium, Schenectady, February 4, 1938, by
Tuve on "The structural forces of atomic nuclei"; Chevy Chase Masonic
Lodge, February 9, 1938, by Tuve on "The new Atomic-Physics Laboratory
and its work"; Washington Physics Colloquium, February 16, 1938, by Teller
on "The origin of galaxies in an expanding universe"; Carnegie Institution
Lecture, Washington, March 1, 1938, by Tuve on "The forces which govern
the atomic nucleus"; Washington Section, American Institute of Electrical
Engineers, March 8, 1938, by Tuve on "Investigating the structural forces of
the atomic nucleus with high voltages" ; Philosophical Society of Washington,
April 9, 1938, by Gamow on "The fourth Washington Conference on Theo-
retical Physics"; Washington Meeting, American Physical Society, April 28,
1938, by Heydenburg on "The scattering of protons and deuterons by deu-
terium and by helium"; Washington Meeting, American Physical Society,
April 29, 1938, by Roberts on "The formation of Be7."

COOPERATION IN NUCLEAR PHYSICS AT UNIVERSITY OF WISCONSIN

Professor G. Breit, of the University of Wisconsin, continued as research
associate and consultant. The following paragraphs summarize briefly
work done by him and his associates at the University of Wisconsin.

Proton-proton scattering. Work has been continued on the theory of
scattering of protons by protons. Previous calculations in connection with
the measurements of Tuve, Heydenburg, and Hafstad have given a fairly
complete picture of the theoretical possibilities in the region up to 1000 kv.
Computations were made on the effects of various types of interaction in
the higher-energy region up to 2800 kv and work is in progress for energies

DEPARTMENT OF TERRESTRIAL MAGNETISM 273

up to 10,000 kv. The calculations show a greater sensitivity of observed
scattering to range than in the lower-energy region. [Some of the results
are shown in comparison with the measurements of Herb, Parkinson, and
Kerst in figures 1, 2, Review of Scientific Instruments, vol. 9, p. 63, 1938.]
Above 1400 kv these measurements show a marked deviation from the type
of dependence of scattering on angle that is to be expected owing to the
phase-shift K0 that represents the spherically symmetric scattering anomaly.
The direction of the deviations is such as would be expected for repulsive
interactions of angular momentum 1 (p-anomaly) and attractive inter-
actions of angular momentum 2 (d-anomaly) in units %. Neither these data
nor newer observations obtained and available from the Department of
Terrestrial Magnetism offer convincing proof of the existence of the p-
and d-waves. The dependence of the observed deviation on angle is such
that one needs both the p- and d-waves, and their variation with energy
is such that it does not appear to be reasonable theoretically. Newer meas-
urements by Herb and collaborators are being made.

The coupling between anomalies with different values of the orbital
angular momentum due to terms of the type (g^) (o2r) had to be con-
sidered in this connection because it might be expected to cause a c?-wave
anomaly at lower energies than if the spin-radius coupling were absent.
The absence of a 3£-condition of colliding protons which follows from the
exclusion principle causes a disappearance of first-order effects of this
type and speaks for the reliability of estimates of p- and d-wave anomalies
by the more elementary methods previously used. The above work was
done in collaboration with Thaxton and Eisenbud. Simplifications for
carrying out computations of Coulomb wave-functions by means of a
numerical evaluation of a definite integral have been made in collaboration
with L. Hoisington. The above work was done in preparation for analysis
of newer data when these should be available.

Fine structure of nuclear levels and relativity. The fine structure of
atomic levels is understood at present as a relativistic effect. It is prob-
able that nuclear levels have a fine structure of a similar origin. In order
to understand the possible effects it was necessary to consider the possible
relativistic effects for forces of non-electromagnetic origin. For relatively
low velocities it was possible to develop such a theory. Some of this was
mentioned in the annual report for 1936-37. Since then the mathematical
structure of the theory was somewhat enlarged by considering the collision
between particles. Possible types of interactions have been set up that
give in the first order of Born's method results that are consistent with
restricted relativity for any velocity of the colliding particles. Other re-
lated forms have been shown to give invariant descriptions of the collision-
process for the exact solution of the wave-equation but with the restriction
to first-order effects in v2/c2 where v is the velocity. These considerations
suggest the presence of interactions of the spin-radius and the spin-spin
type that have been mentioned in the section on proton-proton scattering.

Consequences of this theory for the relativistic effects of the deuteron
have been studied in collaboration with S. Share. It was found that the
possibilities left open by the theory allow considerable latitude in the value

274 CARNEGIE INSTITUTION OF WASHINGTON

of the correction. This shows up an intrinsic uncertainty in the value of
the binding energy due to non-relativistic effects. The exact fitting of the
binding energies of H3, He4 by assumed forces neglecting relativistic effects
appears therefore to be questionable.

The spin-orbit interactions that follow from the above theory have been
computed, using approximate wave-functions, for the ground state of Li7
in collaboration with J. R. Stehn. It was found possible to obtain a fit
to the supposed value of the splitting of the ground-level (~450 kv). The
fit was not obtained, however, by using the simplest form of the theory and
the interpretation of the first excited level of Li7 as a fine-structure com-
ponent of the ground-level is somewhat open to doubt. This doubt is
strengthened by the study made by Rumbaugh, Roberts, and Hafstad on
the relative intensities of the proton groups from Li6 -f- H2 and the slight
indication present in the data of Cockroft and Lewis of a more closely spaced
fine-structure in C13.

Saturation- conditions. If the forces of attraction between nuclear par-
ticles were due to ordinary potentials, the binding energy of nuclei would
increase at least as fast as the square of the atomic number. There would
then be in Nature very heavy stable nuclei. This is contrary to experience.
For this reason exchange-forces are introduced into nuclear theory. There
are at present three types of most commonly used exchange-forces and the
potential energy between two nuclear particles is supposed to be a sum of
an ordinary potential and these three types of exchange-forces. The pos-
sible overstability of heavy nuclei must be prevented by a judicious choice
of the coefficients of the four types of potential. These conditions are
called saturation-conditions because the overstability of heavy nuclei can
be prevented by having saturation of the binding capacity of the nuclear
particles.

Some conditions have been previously known to be necessary and some of
them have been known to be sufficient for saturation. In collaboration with
E. Wigner the necessary and sufficient conditions have been ascertained
and systematized, making use of additional approximate information deriva-
ble from the nonexistence of stable nuclei heavier than N14 with odd atomic
number and even atomic weight. The saturation-conditions can be rep-
resented in a two-dimensional diagram which then shows also the probable
proportions of the four types of interaction.

Calculations were made in collaboration with E. Wigner on the disinte-
gration of Li8 into two alpha particles (Rumbaugh, Roberts, and Hafstad)
and an electron. The approximate effect of resonance to the first excited
state of Be8 is estimated. These calculations are not quite finished.

Calculations are in progress in collaboration with J. Knipp on the capture
of the K-electron by Be7 discovered by Rumbaugh, Roberts, and Hafstad
at the Department of Terrestrial Magnetism. They give evidence that
the mass-difference (Be7 — Li7) cannot exceed the 2-mc2 requisite for posi-
tron emission by more than 60 kv on the Fermi theory and 200 kv on the
Konopinski-Uhlenbeck theory. They also indicate that the many-body
aspect of the nucleus becomes noticeably more important from atomic weight
7 to 11.

DEPARTMENT OF TERRESTRIAL MAGNETISM 275

Isotope-shift. Meissner's observations on the isotope-shift of Mg are
interpreted as a mass-effect enhanced by a perturbation of the ^-configura-
tion by the sd-configuration.

FIELD-WORK AND REDUCTIONS
LAND MAGNETIC SURVEY

The collection, compilation, and discussion of data pertaining to the world
magnetic survey were continued. Green, Chief of Section, was in charge at
Watheroo Magnetic Observatory, while at the office Wallis gave full time
and Forbush, Johnson, and Vestine gave part time to this work. Parkinson
did field-work in the Pacific islands, Australia, Malaya, Siam, Indo-China,
and Dutch East Indies. Wallis and Vestine have well under way prepara-
tion of manuscript on land-results from 1927.

Cooperation was continued with the Aerial, Geological, and Geophysical
Survey of Northern Australia through the loan of magnetometer-inductor
18, and with the Adelaide Observatory of South Australia through the loan
of magnetometer 6. Some magnetic data in the Arctic were obtained in co-
operation with the MacGregor Arctic Expedition.

FIELD-OPERATIONS AND COOPERATIVE SURVEYS

Brief acccounts of field-operations referred to above are given in more
detail below.

Africa. Secular-variation data were obtained through control-observations at the
Cape Town Magnetic Observatory.

Upon request the detailed results of observations made in Portuguese East Africa
and neighboring territories, with descriptions of stations, were supplied to the Director
of the Lourengo Marques Observatory. Similar compilations of data in South
Africa, Southern Rhodesia and Northern Rhodesia, and Portuguese East Africa were
supplied upon request to the Director of the Magnetic Survey of South Africa.

Asia. The following stations were occupied by Parkinson : six stations in Malaya,
namely, Singapore, Malacca, Kuala Lumpur, Ipoh, Penang, and Alor Star; five sta-
tions in Siam, namely, Tung Song, Chumphon, Hua Hin, Bangkok, and Aranya Pra-
desa; five stations in Indo-China, namely, Siemreap, Pnom Penh, Saigon, Hanoi, and
Vinh. At Chumphon the high value of horizontal intensity of 0.40759 CGS was ob-
served. On the return to Australia, a stop was made at the Batavia Magnetic Observa-
tory in order to compare magnetometer-inductors 13 and 28 with the observatory-
standards and to redetermine instrumental constants. No. 13 had previously been sent
to China for use in the magnetic survey of that country in cooperation with the Re-
search Institute of Physics, Academia Sinica, Shanghai. Subsequently, it was seen that
disturbed conditions in China would prevent further field-work there for some time to
come. No. 13 was therefore shipped to Batavia for use in the intercomparison and
constant-determination program, after which this instrument was forwarded to Dr.
A. Walter, Director, British East Africa Meteorological Service, for use in the mag-
netic survey of East Africa. After completing the work at Batavia, Parkinson sailed
for Fremantle on July 6, 1938.

Australasia and Pacific islands. The extensive program of field-work in Australasia
and the Pacific islands, inaugurated in 1936, was continued by Parkinson. In July 1937,
observations were made at Honolulu Magnetic Observatory for the intercomparison

276 CARNEGIE INSTITUTION OF WASHINGTON

of magnetometer-inductors 13 and 28 and the standards of the Observatory. En route
from Honolulu to Sydney, magnetic observations were made at Suva, Fiji Islands.
Following a reoccupation of the magnetic station at Blacktown, near Sydney, another
expedition into the Pacific resulted in the occupation of the following stations : three
stations in New Hebrides, namely, Luganville, Port Patterson, and Port Vila; four
stations in Tahiti, namely, Papeete, Tautira, Taravao, and Motu-Uta; two stations
in New Caledonia, namely, Noumea and Bourail. After returning to Sydney, the
magnetic station at Blacktown was reoccupied for a recomparison of magnetometer-
inductors 18 and 28, the former instrument being used by Richardson of the Aerial,
Geological, and Geophysical Survey of Northern Australia. On the way to Asia,
Parkinson stopped at the Watheroo Observatory for a recomparison of his instrument,
No. 28, with the standards of the Observatory. Stops were also made at Carnarvon
and Port Hedland, on the "Western Australian coast, to reoccupy repeat-stations.

L. A. Richardson, of the Aerial, Geological, and Geophysical Survey of Northern
Australia, using magnetometer-inductor 18, occupied six stations in the Northern
Territory of Australia, namely, Taylor's Crossing, Barrow Creek, Ryan's Well, Alice
Springs, Daly Waters, and Newcastle.

The usual control-observations for the records obtained at the Watheroo Magnetic
Observatory were maintained.

North America. Maintenance of International Magnetic Standards of the Depart-
ment was continued in cooperation with the United States Coast and Geodetic Survey,
at the Cheltenham Magnetic Observatory, where CIW sine-galvanometer 1 and CIW
Schultze earth-inductor 48 were used as standards for horizontal intensity and in-
clination.

South America. Secular-variation data were obtained by the control-observations
made regularly at the Huancayo Magnetic Observatory. A compilation of magnetic
declination observed by the Department was supplied for use of the Argentine Avia-
tion Service.

OBSERVATORY-WORK

Johnston continued in charge of the Section of Observatory- Work. The
magnetic reductions and compilations were maintained with the assistance of
McNish, Ledig, Scott, and Miss Balsam. Wait and Torreson made excellent
progress in the reduction and tabulation of the atmospheric data in con-
ductivity and potential-gradient from both observatories. The members
of the staff engaged at the observatories are mentioned in the respective
reports.

The observatories at Huancayo (Peru) and Watheroo (Western Australia)
continued the extensive geophysical program. Both obtained continuous
records of the magnetic elements and magnetic activity was very marked as
the peak of the sunspot-cycle was reached during the year. At Huancayo
during the exceptionally violent magnetic storm of April 16, 1938, the re-
markable range of 1350 gammas occurred in horizontal intensity. This
severe storm was completely recorded since an .H-variometer of low sensi-
tivity had fortunately been placed in operation in June 1937. The height of
the ionosphere was continuously recorded at both observatories. Until
November 1937 at Huancayo and May 1938 at Watheroo the records were
obtained with a fixed-frequency apparatus at 4800 kc/sec with manual-
controlled multifrequency observations twice a week. After the dates men-
tioned the ionospheric records were obtained with automatic multifrequency

DEPARTMENT OF TERRESTRIAL MAGNETISM 277

equipment, developed in the Department, capable of continuous operation.
A frequency-range of 516 to 16,000 kc/sec is completely covered every fifteen
minutes. In the short time that the multifrequency equipment has been
operating a large amount of valuable data has been accumulated.

Observations in atmospheric electricity, meteorology, and earth-currents
were obtained at both observatories. They also made daily observations,
weather permitting, with the Hale spectrohelioscope at stated times so as
to tie in with the solar-disturbance program of the International Astronomical
Union for worldwide continuous observations of the Sun. Both observatories
continued to send weekly reports by radio of half-day magnetic activity
to assist the Department in its preparation of the American magnetic
character-figure. Huancayo in addition obtained continuous records with
a three-component seismograph and a Compton precision cosmic-ray meter.

Cooperative work was continued with other observatories. The MacGregor
Arctic Expedition established a magnetic observatory near Reindeer Point, at
Etah, Greenland, using materials and apparatus supplied by the Department.
The cooperative program in atmospheric electricity and earth-currents was
maintained at Tucson, Arizona, with the assistance of the United States
Coast and Geodetic Survey and Bell Telephone Laboratories. With the
help of the Department of Scientific and Industrial Research of New Zealand,
the atmospheric-electric observations were continued at Apia Observatory,
Samoa. The Department supplied forms for observatory- and field-work
to the magnetic observatory at Cape Town, South Africa. Cheltenham
Magnetic Observatory operated the CIW vertical-intensity inductometer
during the year and utilized the Department's sine-galvanometer and stand-
ard Schulze earth-inductor for standardizations in horizontal intensity and
inclination, respectively.

OPERATIONS AT OBSERVATORIES

The operations during the report-year at the observatories of the Depart-
ment and at observatories with which the Department cooperated are sum-
marized below.

Watheroo Magnetic Observatory, Western Australia. The Watheroo Magnetic
Observatory is situated in latitude 30° 19'1 south and longitude 115° 52'6 east of
Greenwich, 244 meters (800 feet) above sea-level.

The Eschenhagen magnetograph was operated continuously with only a few hours
loss of record caused by the lamp having burned out.

Scale-value determinations for the horizontal-intensity variometer, using the deflec-
tion-method, were made once each month and the value has remained remarkably
constant throughout the year. Vertical-intensity scale-value observations were made
daily by the electrical method. The monthly mean scale-value for both the horizontal
and vertical components of the Earth's field for the calendar year 1937 are shown
in table 1.

The La Cour rapid-running magnetograph was in continuous operation with the
exception of short periods from time to time when the driving mechanism failed, when
adjustments were necessary, or when the light failed. Scale-value determinations by
the electrical method were made monthly as in previous years and in the case of the
i^-instrument were fairly constant. Some fluctuations occurred in the scale-value of
the Z-variometer, the values tending to increase toward the middle of the year and

278

CARNEGIE INSTITUTION OF WASHINGTON

Table 1. Scale-values of magnetographs, Watheroo Magnetic Observatory, 1987

Scale-values

> in 7/mm

Month

Eschenhagen

La Cour

H (reduced
to base-line)

Z (means
daily values)

January

2.35
2.36
2.34
2.36
2.36
2.35
2.36
2.36
2.35
2.36
2.37
2.36

4.13

4.14

4.18

4.29

4.42
4.26,3.74

3.73

3.69

3.77

3.82
3.96,3.28

3.34

4.67
4.64
4.64
4.59
4.60
4.60
4.59
4.65
4.67
4.59
4.38
4.45

2.64
2.82
2.80
2.92
3.06
3.46
2.94
3.11
3.28
3.09
2.70
2.84

February

March

April

May

June

July

August

September

October

November

December

dropping back again toward the close of the year. The values for both variometers,
as derived from the monthly determinations, are given in table 1.

The Mitchell vertical-force inductometer was kept in operation until, on instruc-
tions from the office, it was discontinued December 31, 1937. The galvanometer-
sensitivity and scale-value were determined once each month. Toward the close of
the year there were more or less frequent stoppages of the driving clock and the
record for this period is somewhat fragmentary.

Continuous records of earth-potentials for derivation of diurnal variation of earth-
currents were made over the system of electrodes as described in previous reports.
A few scattered days were lost but the total loss of record was negligible. Pending
the outcome of the result of examination of the record from the new electrode R\
which was installed during August 1936, complete scalings for the short east-west
line were continued.

Air-potentials have been recorded continuously by means of the standard potential-
gradient apparatus as in former years and the usual monthly "reduction-factor" deter-
minations have been made. The mean value, 1.10, agrees well with those determined
in earlier years.

Positive and negative air-conductivities were recorded and the usual control-obser-
vations were made regularly. Table 2 gives preliminary values of the atmospheric-
electric elements as recorded in 1937.

The ionospheric equipment operated continuously. Determinations of layer-heights
and of critical frequencies were made in accordance with a regular schedule. The
fixed-frequency automatic recorder was in continuous operation with the exception
of those periods when multifrequency determinations were being made by manual
operation. The multifrequency runs were made in accordance with a regular pro-
gram. Results of preliminary reduction of the observational data were forwarded
to Washington at regular intervals, brief reports of the results of these runs, consist-
ing of layer-heights and critical frequencies, having been forwarded by radiograms,
frequently on the day the run was made, and largely through station W3AMS at
Washington Grove, Maryland, occasional use being made of station W6GHD in
California and W3QP in Pennsylvania. Communication-schedules were maintained
between the Observatory and Washington through the cooperation of the above-
mentioned stations with only infrequent interruptions throughout the year. From

DEPARTMENT OF TERRESTRIAL MAGNETISM

279

TjyBLfi 2. Preliminary monthly mean values of atmospheric-electric elements, Watheroo

Magnetic Observatory, 1937

Number

of selected

days

Potential-gradient

Air-conductivity, unit 10"4

2SU

Month

Reduction
factor

Value in
v/m

X-

X++X-

X+/X-

January

22
16
16
18
18
21
27
25
24
16
21
21

1.08
1.11
1.09
1.13
1.12
1.22
1.09
1.14
1.04
1.04
1.00
1.10

94.7
98.4
94.3
72.6
70.2
73.6
70.0
78.6
85.6
90.4
90.9
107.2

1.60
1.51
1.60
2.06
2.17
2.22
2.47
2.07
1.94
1.72
1.61
1.57

1.53
1.36
1.52
1.96
1.89
1.94
2.19
1.80
1.68
1.52
1.49
1.64

3.13

2.87
3.12
4.02
4.06
4.16
4.66
3.87
3.62
3.24
3.10
3.21

1.05

February

1.11

March

1.05

April

1.05

May

1.15

June

1.14

July

1.13

August

1.15

September

October

1.15
1.13

November

1.08

December

0.96

Total and means .

245

1.10

85.5

1.88

1.71

3.59

1.10

July 1, 1937, to June 30, 1938, some 300 messages dealing with scientific results were
sent from the Observatory to the office. Magnetic character of days was reported
to the office weekly by this means.

After some changes relative to facility of handling of the Hale spectrohelioscope
and after some experimental work in October 1937, this instrument was regularly used
beginning November 1. Observations were made following the international program
covering this work and the records and summarized report were forwarded to the
office at the close of each month.

The usual meteorological observations, including sunshine-records, nuclei-count,
etc., were made daily and all the self-recording meteorological instruments were kept
in continuous operation. Data were supplied monthly to the Commonwealth Weather
Bureau in Melbourne as in former years.

At the close of the calendar year 1937 the tabulation and reduction of observatory-
data were well in hand.

A summary of the results of magnetic observations obtained during the year indi-
cates that conditions are very similar and changes taking place are approximately
of the same order as those indicated in previous reports. The preliminary mean
values of magnetic elements for all days of 1937, as deduced from the Eschenhagen
magnetograms, referring the elements to the north-seeking end of the needle and
reckoning east declination and north inclination as positive, are: declination, —3°
3K8; horizontal intensity, 0.24676 CGS unit; vertical intensity, —0.51445 CGS unit;
and inclination, —64° 22'5. These results indicate annual changes as follows: declina-
tion, +5.4; horizontal intensity, —1 gamma; vertical intensity, —33 gammas; and
inclination, — CK9.

The grounds, buildings, and equipment were kept in order and necessary repair
work was done as occasion demanded. An extra roof has been built over the iono-
spheric laboratory as a means of protecting the equipment from the intense heat of
the Australian summer. The attic room in the main quarters was insulated and re-
finished, making it much more comfortable and convenient.

Early in April 1938 the new ionospheric equipment, consisting of a multifrequency
recorder, was received from Washington. By June 30, 1938, the installation of this

280 CARNEGIE INSTITUTION OF WASHINGTON

new equipment was completed and records were being made using low antenna.
Further calibrations will be made when the high antenna is erected.

Green continued as Observer-in-Charge. Seaton continued as first assistant and
in charge of the ionospheric work and communications, though for the last half of
the report-year a large part of this work was done by T. K. Hogan, who had been in
training throughout the year 1937. Junior observers L. S. Prior and Noel G. Cham-
berlain have become quite proficient in the various activities of the Observatory and,
assisted by Seaton during the last half of the year, made excellent progress in the
tabulation and reduction of the observatory-results. C. H. George as mechanic gave
excellent service and his work and attention to duty is especially noted. Leslie Aitche-
son was temporarily engaged as carpenter from November 1937 to June 1938. L. V.
Berkner arrived at the Observatory April 10, 1938, to take charge of the installation
of the new ionospheric equipment.

The support and cooperation of various State and Commonwealth departments
have been continued and are hereby gratefully acknowledged. We are especially in-
debted to G. A. Scott, Senior Radio Inspector of the Commonwealth Radio Depart-
ment, for his interest and kindly assistance in the matter of obtaining permission
to operate the new multifrequency equipment. Particular mention should be made
of the Department of Trade and Customs of the Commonwealth of Australia for
kindness and assistance in the matter of importation of equipment. The various
officials of the Customs Department of Western Australia have been most helpful
in the matter of handling our importations. We are greatly indebted to Professor
A. D. Ross of the University of Western Australia for his interest, advice, and assist-
ance with matters pertaining to the Observatory at various times throughout the year.

Huancayo Magnetic Observatory. The Observatory is situated in latitude 12°
02'7 south and longitude 75° 20'4 west of Greenwich, in the central valley of the
Peruvian Cordillera at an elevation of 3350 meters (11,000 feet) above sea-level.

F. T. Davies was Observer-in-Charge through the year. W. E. Scott was first
assistant until September 23, 1937, when he returned to Washington. H. E. Stanton
continued as observer through the year. W. Culmsee joined the staff from the
Watheroo Observatory on September 1, 1937. H. W. Wells returned to the Observa-
tory on October 8, 1937, as first assistant. T. Astete and A. Macha continued as
clerical assistants during the year.

Two magnetographs, one an Eschenhagen, the other a La Cour rapid-run type,
were operated continuously. Control of base-lines was obtained by weekly absolute
magnetic observations. Scale- values for horizontal intensity and vertical intensity
of the La Cour magnetograph were determined electrically once each month. Scale-
values for declination and horizontal intensity of the Eschenhagen magnetograph
were determined electrically once each week. The vertical intensity scale-value of
the Eschenhagen magnetograph was determined electrically three times each week.
In addition to the three Eschenhagen variometers, an additional La Cour H vari-
ometer was operated at low sensitivity, recording on the Eschenhagen magnetogram.
Monthly reports of the more important magnetic disturbances were sent to Wash-
ington.

Air-potentials were recorded with standard potential-gradient apparatus and scale-
values were determined weekly until December 1937, and biweekly thereafter. Re-
duction-factors were determined monthly by comparison with potentials measured on
open level ground until October 1937 and quarterly thereafter.

Positive and negative air-conductivities were recorded continuously. Scale-values
were measured weekly during 1937 and once every two weeks from January 1, 1938.

Earth-current potentials were recorded by a Leeds and Northrup apparatus. Two
separate systems of north and south, east and west electrodes were used. Lightning
caused occasional stoppages of the apparatus.

DEPARTMENT OF TERRESTRIAL MAGNETISM

281

Two horizontal-component Wenner-type and one vertical-component Benioff-type
seismographs were in continuous operation. Analyses of important seismic disturb-
ances were made and transmitted by radio to Washington.

A Compton-Bennett cosmic-ray meter recorded cosmic-ray intensities during the
year. In April 1938 the panel of this meter was changed to allow of greater facility in
getting at the batteries and connections. The hourly-zero relay was changed also.

Visual observations of the Sun were made daily with the Hale spectrohelioscope
whenever conditions permitted. The assigned periods of observation for this Observa-
tory are 15h 30m to 16h 00m and 16b 30m to 17h OCT GMT. Monthly reports of
spectrohelioscopic observations were sent to Washington.

Automatic recording of ionospheric heights was maintained during the year.
Until October 29 this was done by the older equipment functioning at a fixed
frequency, with regular series of manually operated varying-frequency tests to
supplement the records. A new multifrequency automatic recorder was installed
in place of the fixed-frequency recorder during November to December 1937. The
multifrequency apparatus, with a few minor adjustments, has functioned well
since installation. Tabulations of critical frequencies and heights for the various
layers were made monthly as well as analyses of the data. Quarterly reports on
ionospheric conditions were sent to Washington.

Observations of barometric pressure, maximum and minimum temperatures,
relative humidity, rainfall, cloudiness, wind-direction, and wind-velocity were made
daily at 8h 75° west meridian time. Measurements of condensation-nuclei were
made daily at the same hour. Continuous records were obtained with barograph,
thermograph, hygrograph, anemograph, and sunshine-recorder. Computations of
and tabulations of magnetic, atmospheric-electric, earth-current, ionospheric, and
meteorological studies were kept current, the traces and tabulations being forwarded
to Washington monthly, together with seismograms and spectrohelioscopic records.
A new recording micro-barograph, purchased from Negretti and Zambra of London,
was installed in the Atmospheric-Electricity Building in March 1938. The standard
barometer and ordinary barograph were moved from the office to the Atmospheric-
Electricity Building in March. A thermograph is in continuous operation in this

Table 3. Preliminary monthly mean values of atmospheric-electric elements, Huancayo

Magnetic Observatory, 1937

Number

of selected

days

Potential-gradient

Air-conductivity, unit 10 4 <

;su

Month

Reduction
factor

Value in
v/m

X-

X++X-

X+/X-

January

15
11
10
10
23
21
23
20
12
20
10
14

1.15
1.16
1.15
1.17
1.16
1.19
1.20
1.14
1.14
1.14

50.5
55.4
45.0
51.4
47.6
48.6
53.4
48.1
45.8
58.6
48.1
47.3

3.55
3.62
4.31
3.60
4.43
4.74
4.35
3.94
4.86
3.50
4.49
4.81

3.48
3.44
4.21
3.59
4.49
4.83
4.42
3.97
4.83
3.56
4.22
4.95

7.03
7.06
8.52
7.19
8.92
9.57
8.77
7.91
9.69
7.06
8.71
9.76

1.02

February

1.05

March

1.02

April

1.00

May

0.99

June

0.98

July

0.98

August

0.99

September

October

1.01
0.98

November

1.06

December

0.97

Total and means .

189

1.16

50.0

4.18

4.17

8.35

1.00

282 CARNEGIE INSTITUTION OF WASHINGTON

room also. The micro-barograms were scaled and tabulated monthly. Tabulations
of barometric pressure, wind-direction, wind-velocity, and sunshine, together with
summaries of the meteorological data taken at 8h daily, were forwarded each month
to the Servicio Meteorologico Nacional del Peru and also, by request, to the Centro
Geografico Departamental de Junin.

Preliminary mean values of the magnetic elements for all days of 1937 as deduced
from the Eschenhagen magnetograms, referring the elements to the north-seeking
end of the needle and reckoning east declination and north inclination as positive,
are: declination, -|-70 08'3; horizontal intensity, 0.29593 CGS unit; vertical inten-
sity, +0.01165 CGS unit; and inclination, +2° 15'3. The preliminary values for
the annual changes in the magnetic elements, based on these values and on the final
values for 1936, are: — 3'3 in declination; —16 gammas in horizontal intensity;
-f-15 gammas in vertical intensity; and +1'8 in inclination.

Preliminary monthly mean values of the atmospheric-electric elements are given
in table 3. The mean value, 1.16, of the reduction-factor for potential-gradient
records agrees closely with previous values, which for the years 1934, 1935, and
1936 were 1.16, 1.18, and 1.17, respectively. There were 189 selected days for which
the atmospheric-electric elements were derived during the year. The preliminary
mean value of potential-gradient for 87 days during the dry season was 49.4 volts
per meter and for 102 days in the wet season was 50.3 volts per meter.

Many courtesies were extended the Observatory and its staff by the governmental
officials and departments of Peru and by local provincial and municipal authorities.
The success of the year's work has also been furthered by the cordial attitude of the
Ambassador and the Consul-General to Peru of the United States.

COOPERATION WITH OTHER OBSERVATORIES

Apia Observatory, Western Samoa. Cooperation of the Department with the
Apia Observatory (latitude 13° 48' south, longitude 171° 46' west) in the fields of
atmospheric electricity and terrestrial magnetism was continued. The program of
work at the Observatory also includes seismology and meteorology.

The work in terrestrial magnetism consisted of absolute measurements of horizontal
intensity, declination, and inclination, together with the continuous operation of auto-
graphic instruments for recording the variations in horizontal intensity, declination,
and vertical intensity.

The instruments used for absolute observations were CIW magnetometer 9 (on
loan through the courtesy of the Department of Terrestrial Magnetism) and Schulze
earth-inductor 2. The autographic records were obtained by means of two Eschen-
hagen variometers for horizontal force and declination and a Godhavn balance for
vertical intensity. The continuity of the records was interrupted for a period of
three months, commencing in July 1937, when the roof of the Gauss House was under
repair. Minor interruptions were caused by the appearance of slender fibers (thought
to be fungoid growth) in the Eschenhagen variometers.

The revision of the declination-measurements for the period 1932-1934, rendered
necessary by the discovery in 1935 of a defect in the old Tesdorpf magnetometer,
was completed.

Potential-gradient measurements with the Benndorf electrometer were continued
during the year. Absolute observations during the dry season of 1937 showed that
the fall of a tree in the vicinity of the potential-gradient building had not affected
the value of the reduction-factor. The leak-free potentiometer-method due to Gish
and Sherman has been used, since March 1938, in experiments to determine the reduc-
tion-factor. The value 1.00 has been adopted for this factor as in previous years.

During 1937 there were 89 zero-days with a mean value of 123 volts per meter.

DEPARTMENT OF TERRESTRIAL MAGNETISM

283

The mean values, expressed in volts per meter, of the potential-gradient were as
follows: January, 120; February, no zero-days; March, 97; April, 113; May, 115;
June, 127; July, 133; August, 121; September, 124; October, 122; November, ISO-
December, 147.

The seismographs, which were originally installed at Apia more than thirty years
ago, were maintained in use. Some slight modifications of design which were intro-
duced in July 1937 improved the scope of the records. During the year ended June
30, 1938, 244 seismic disturbances were recorded.

The routine work in meteorology comprised surface-observations made twice a
day and frequent measurements of upper winds. Climatological summaries were also
prepared and synoptic charts of the weather in the southwest Pacific Ocean were
plotted every day. Storm- warnings were issued when necessary with the general
collective broadcast of weather-reports from the Apia Radio Station.

Table 4. Meteorological summary, Apia Observatory, 1937

Month

Pressure

Temp.

Rainfall

Humidity
(9 a.m.)

Sunshine

Wind

inches
29.744
29.779
29.769
29.814
29.872
29.867
29.861
29.861
29 . 902
29.866
29 . 799
29 . 767

80.2
80.3
79.3
80.0
79.0
78.8
79.0
78.8
78.4
79.2
79.7
79.7

inches

15.20

15.85

16.15

9.41

15.59

0.65

2.02

6.26

5.46

9.28

4.56

11.17

per cent
80
81
81
80
77
76
76
78
74
77
74
76

hours
220.7
151.5
187.2
212.2
218.0
245.7
259.7
223.4
223.2
205.5
225.1
192.5

miles /hr
7.4

February

7.6

March

5.9

April

6.3

May

7.5

June

7.9

July

7.8

August

11.0

September

6.9

October

8.4

November

5.8

December

5.4

Mean or total

29.825

79.4

111.60

2564 . 7

7.3

J. Wadsworth, who had been the Director since September 1, 1930, resigned in June
1938 and left Apia on June 9. H. B. Sapsford assumed control as Acting Director.
J. M. Austin, C. W. Tremewan, and A. B. F. Ayers joined the professional staff of the
Apia Observatory during the year.

Tucson Magnetic Observatory, United States. Observer-in-Charge J. Hershberger
with the assistance of R. F. White, both of the staff of the United States Coast and
Geodetic Survey Tucson Magnetic Observatory, operated the Department's appa-
ratus for recording atmospheric potential-gradient and positive and negative air-
conductivities. Mrs. G. Dewey, employed by the Department on part-time basis
at the Observatory, reduced these records. Nine observations were made of the
potential-gradient reduction-factor, giving a mean value of 1.23 for reduction of
observed values to volts per meter. Table 5 summarizes the monthly and annual
values of the atmospheric-electric elements.

Registration of earth-currents was continued using the new electrodes installed
in the last report-year. The Bell Telephone Laboratories specially leased a line for
connection to the Wilcox electrode. Earth-current activity was specially marked
during the sunspot-maximum prevailing, and in consequence much trace was lost.
Unfortunately a galvanometer of low sensitivity was not available for the recording.

Magnetic Branch, Trigonometrical Survey, Union of South Africa. Cooperation
with the Magnetic Branch of the Trigonometrical Survey of the Union of South

284

CARNEGIE INSTITUTION OF WASHINGTON

Table 5. Preliminary monthly mean values of atmospheric-electric elements, Tucson

Magnetic Observatory, 1937

Number

of selected

days

Potential-gradient

Air-conductivity, unit 10 4

3SU

Month

Reduction
factor

Value in
v/m

X-

X++X-

X+/X-

January

24
23
24
24
25
25
16
20
23
30
27
29

1.22
1.24

65.3

57.7
48.6
46.9
45.0
52.2
48.7
46.8
44.4
44.7
50.9
54.4

1.77
2.18
2.17
2.15
2.45
2.66
2.52
2.44
2.57
2.66
2.87
2.31

1.58
1.61
2.18
2.28
2.64
2.82
2.38
2.25
2.30
2.39
2.33
2.04

3.35
3.79
4.35
4.43
5.09
5.48
4.90
4.69
4.87
5.05
5.20
4.35

1.12

February

1.35

March

1.00

April

1.25
1.29
1.22
1.20
1.22

0.94

May

0.93

June

0.94

July

1.06

August

1.08

September

October

1.12

1.20

1.11

November

1.23

December

1.27

1.13

Total and means .

290

1.23

50.5

2.40

2.23

4.63

1.08

Africa was continued in the operation of the Cape Town Magnetic Observatory. A
CIW magnetometer-inductor is on loan for control of magnetograms. Dr. A. Ogg,
Magnetic-Survey Adviser, was supplied with details and particulars regarding
field- and observatory-work.

Royal Alfred Observatory, Port Louis, Mauritius, Indian Ocean. The loan of
equipment, including a CIW marine inductor and galvanometer for control of
vertical-intensity records at the Royal Alfred Observatory, Mauritius, was continued.

College, Alaska. Professor E. H. Bramhall continued work in the laboratory
preparing equipment for recording of ionospheric conditions. The volume "Auroral
research at the University of Alaska, 1930-1934" (volume 3 of the miscellaneous
publications of the University) was edited and seen through the press by Fleming
in an edition of 1000, of which 575 copies have been sent interested investigators
and organizations.

Etah Magnetic Observatory, Greenland. The MacGregor Arctic Expedition was
at winter base at Etah, Greenland, from September 1937, and the whole party was
busily engaged in prosecuting the magnetic, meteorological, auroral, and exploratory
programs. The CIW magnetic station of 1908 and 1923 at Reindeer Point, near
Etah, was reoccupied to determine secular variation.

The non-magnetic observatory with its walls, roof, and floor thickly covered with
Balsam Wool for insulating purposes was completed by September 15, 1937, and
the magnetographs were installed one week later by Roy Fitzsimmons, magnetician
of the Expedition. Since then continuous records of the magnetic elements have
been obtained. (The station was dismantled at midnight July 5, 1938.) The Expe-
dition sent by radio weekly reports of observed magnetic activity to the Department
of Terrestrial Magnetism in Washington, D. C, and these were broadcast weekly
from Washington and were published weekly in the Science Service Research Aid
Announcements.

Surface meteorological observations were obtained at hourly intervals. Eight
o'clock morning and evening reports were sent to the United States Weather Bureau
giving barometric pressure, pressure characteristic, weather, wind-direction and
wind- velocity, observed air- temperature, and maximum and minimum temperatures.
Pilot balloons were flown twice daily, weather permitting. Unusually warm weather

DEPARTMENT OF TERRESTRIAL MAGNETISM 285

prevailed, the lowest average temperature being —30° C. Winds were unusually
high. The auroral program consisted of visual observations and 45 photographs were
obtained. The wind-driven generators for charging the storage-batteries proved
quite efficient.

The weather was not very satisfactory for flying; however, Commander Schloss-
bach made two successful reconnaissance-flights. In the first he flew alone over the
supposed Crocker Land area and saw no signs of this land. In a later flight Ellesmere
Island was thoroughly explored from the air and some unusually high mountain peaks
were discovered.

Owing to the unusually mild winter solid ice did not form in Smith Sound, and
therefore many sledge-trips were made in northern Greenland. Roy Fitzsimmons
and Paul Furlong finally succeeded in crossing to Cape Sabine in April and made
magnetic observations. The Expedition plans to return to New York in the summer
of 1938.

Cheltenham Magnetic Observatory, United States. Cooperation at the Chelten-
ham Magnetic Observatory of the United States Coast and Geodetic Survey was
continued. CIW instruments used for maintaining standards and for test included
the following: Sine-galvanometer 1 and earth-inductor 48 for control of standards
in horizontal intensity and inclination; perminvar vertical-intensity induction-
variometer for test of method; Compton-Bennett precision cosmic-ray meter 1
for automatic recording of cosmic-ray intensity. Observer-in-Charge Ludy and
G. Hartnell of the staff of the Observatory gave generously of their time and skill
in these cooperative endeavors. The National Bureau of Standards carefully recali-
brated the standard cells and potentiometer at the Observatory to check upon their
behavior in connection with sine-galvanometer performance; as in the previous year
the resulting correction to computed values because of slight change in calibrations
is quite small, the total correction being only —0.5 gamma.

Meteorological Office, Wellington, New Zealand. CIW Aitken nuclei-counter 7
was on loan throughout the report-year to Dr. Edward Kidson, Director of the
Meteorological Office at Wellington, New Zealand. Summaries of data obtained
there by C. G. Green of Dr. Kidson's staff from July 1937 through March 1938 were
received.

Stanford University, California. CIW Aitken nuclei-counter 6 was ioaned for
some six weeks to Professor N. E. Bradbury of the Department of Physics of
Stanford University for comparison with and calibration of that Department's newly
constructed recording nuclei-counter.

REDUCTION OF MAGNETIC DATA

The Section of Observatory-Work was actively engaged in the reduction
of the accumulated magnetic data from the Watheroo and Huancayo observ-
atories. The final revised results of Watheroo for the year 1935 were added
to the manuscript of Watheroo data for the years 1919 to 1934. The Huan-
cayo data were completely reduced for the year 1936. Work is now pro-
gressing on the current magnetic observations from both observatories.

The new measure of activity in the Earth's magnetic field, the American
character-figure Ca, was compiled throughout the report-year. The data
were statistically examined and the character-figure was shown to be a
precise measure. It represents worldwide magnetic conditions with rela-
tively high fidelity. A close relation exists between the American and inter-
national character-figures. A correlation-coefficient of 0.70 was found
between this new measure and the radio transmission-disturbance figure

286

CARNEGIE INSTITUTION OF WASHINGTON

for the circuit, New York to London, of the Bell Telephone Laboratories.
Because of this high correlation the information derived from study of
variations in terrestrial magnetism over the past century may be applied
to problems in radio communication. The American character-figure dis-
criminates very exactly between degrees of magnetic activity on highly
disturbed days when radio communication is most affected.

The final values of the magnetic elements for 1936 and the preliminary
values for 1937 for all days are shown in table 6.

Table 6. Annual values of the magnetic elements at the Watheroo and Huancayo magnetic
observatories as based upon magnetograms for all days

Decli-
nation
D

Incli-
nation
I

Intensity-components

Local

Year

Hori-
zontal
H

Total
F

North-
south
X

East-
west
Y

Vertical
Z

magnetic

constant

Wathekoo Magnetic Observatory

1936

1937

3 37' 1W
3 31.8

64 2lf6S
64 22.5

246777
24676

570287
57057

246287
24629

- 15577
-1519

-514127
-51445

35634
35645

Huancayo Magnetic Observatory

1936

1937

7 llf6E
7 08.3

2 13 .'5N
2 15.3

29609
29593

29631
29616

29376
29364

3708
3677

1150
1165

29615
29599

REDUCTION OF ELECTRIC DATA

Wait, Torreson, and Miss Balsam continued the reduction of atmospheric-
electric records from Watheroo and Huancayo for the 11-year period 1924-
1934 and preparation of the results for offset reproduction in publication.
Besides the hourly mean values of potential-gradient and positive and
negative air-conductivities, the results include electric character-figures and
meteorological data. For Tucson only the preliminary compilations of the
atmospheric-electric data have been prepared by Mrs. Dewey ; final tabula-
tions for publication of these must await completion in 1939 of the mate-
rial from Watheroo and Huancayo.

Rooney kept current the final reductions of the earth-current records at
Watheroo, Huancayo, and Tucson.

OCEANOGRAPHIC WORK
REDUCTIONS OF CARNEGIE DATA

PHYSICAL AND CHEMICAL RESULTS

Final revision of manuscript prepared by Mrs. K. B. Clarke-Hafstad and
added discussion of the meteorological results obtained on the Carnegie
during her seventh cruise were completed by W. C. Jacobs at the Scripps
Institution of Oceanography under the supervision of H. U. Sverdrup, re-

DEPARTMENT OF TERRESTRIAL MAGNETISM 287

search associate. The title of the manuscript is "Meteorological results of
Cruise VII of the Carnegie, 1928-1929" by K. B. Clarke-Hafstad and W. C.
Jacobs. It is planned to publish it as part of volume IV of the series "Re-
sults of oceanographic and meteorological work obtained on board the
Carnegie, Cruise VII, 1928-1929, under the command of J. P. Ault."

BIOLOGICAL RESULTS

Throughout most of the year Graham was occupied at the Hopkins Marine
Station, Pacific Grove, California, in a continuation of studies of the dino-
flagellates of the Carnegie plankton-collections. During June 20 to August
31, 1937, however, he was stationed in Palo Alto at the Division of Plant
Biology of the Carnegie Institution of Washington, where manuscript was
prepared and frequent use was made of the libraries of Stanford University.
Mrs. N. Bronikovski assisted to the end of 1937 in the routine examination
of the plankton-samples and in the preliminary sketching of organisms.
Mrs. Mary Doudoroff was employed from January 1 as artist and labora-
tory assistant to prepare maps and drawings and to assist in preparation
of lists of species, etc.

The routine examination of the plankton-samples for dinoflagellates was
completed for the entire collection. Distributional lists including records
of depth and all chemical and physical conditions of the water observed
were compiled for 76 species. Ranges of conditions for each species were
computed as well as the ranges of surface-temperatures for the record-
stations in an attempt to determine the environmental tolerances of each
species. Particular attention was paid to the depth-distribution and tables
were compiled for each species showing the frequency of sample records
for 0, 50, and 100 m.

The report on the thecal morphology and interrelationships of the mem-
bers of the Peridiniales begun last year was completed under the title
"Studies in the morphology, taxonomy, and ecology of the Peridiniales. "
It deals with 29 different species and varieties of the order which were
examined in considerable detail in connection with skeletal features in
order to gain a better understanding of the natural relationships which
should underlie the classification of the group. The species studied belong
to the following genera: Goniodoma, Ceratocorys, Goniaulax, Acanthogoni-
aulax, Spiraulax, Peridinium, and Ceratium.

In addition to the above report on the interrelationships of the genera
of Peridiniales, a paper was begun on the distribution of the genus Ceratium.
This large genus including 57 species has been given particular attention
in recent oceanographic expeditions because it is the only genus which is
common and at the same time for which there is any approach to a satis-
factory classification. In the Carnegie studies of this genus a minimum
of time was spent on the taxonomy of the group and an attempt made to
correlate the distribution of the species with general oceanographic condi-
tions. This work was almost completed during the report-year.

With the completion of the preliminary census of samples it was possible
to begin a study of the interrelationships between the distribution of the
species and oceanographic conditions in general. This aspect of the study

288 CARNEGIE INSTITUTION OF WASHINGTON

was applied particularly to the 57 species of the genus Ceratium found in
the collection. On the basis of the study of these forms a new phytogeo-
graphic classification was made. This classification may possibly apply
to all oceanic plankton-species. It recognizes only two main groups, namely,
tropical and subpolar, in addition to cosmopolitan species. There are no
temperate species, that is, no species which occur in intermediate lati-
tudes which are not also found as abundantly either in the tropics or in
subpolar regions. The tropical forms vary in their tolerance to subtropical
and temperate conditions so that there are intolerant, slightly tolerant, and
very tolerant tropical species. The distributional limits of the two main
groups are closely correlated with the regions of the subpolar convergence
in both the Atlantic and the Pacific.

Considerable evidence of the isolation of the North Pacific waters was
accumulated from the distribution of the Ceratium species. The subpolar
flora at the northern Carnegie stations in the Pacific was definitely different
from that which is well known to occur in the northern Atlantic and adjacent
subarctic waters.

Particular attention was paid the vertical distribution of Ceratium. The
data of Jorgensen (1920), which he used for the analysis of currents in the
Mediterranean, were shown by Nielsen (1934) to indicate a shade flora
rather than currents. The Carnegie data substantiate the contention of
Nielsen that Jorgensen's "winter species" are in truth shade species. Twenty
of the 57 Carnegie species were found with increasing frequency with in-
crease in depth to 100 m. and are thus shade species; 6 were questionably
so. Most of these species were the same as those designated shade species
by Nielsen. These forms are particularly adapted for life in dimly illumi-
nated regions and show very definite morphological peculiarities. The
advantage of such an adaptation is obviously the ability to utilize the store
of nutrient salts in the subsurface levels.

MISCELLANEOUS

Upon request of the Hydrographer of the British Admiralty, details
regarding atmospheric-electric instruments and program on the Carnegie
were supplied for consideration of the proposed work of the Research. De-
tails were also supplied the Hydrographer regarding the feathering-propeller
design of the Carnegie.

Graham took part in the seminars of the Hopkins Marine Station and
presented two papers, namely, "Evolution in Ceratia" January 7, 1938, and
"On oceanic aspects of Ceratium" July 1, 1938.

INSTRUMENT-SHOP

The personnel of the instrument-shop comprised Steiner (in charge),
Lorz, Haase, A. Smith, Huff, Mitchell, (to January 31, 1938), Fogel (from
February 1, 1938), Malvin, and Quade. They are responsible for the
design and construction of new equipment and experimental apparatus,
and the maintenance of instruments, buildings, and grounds. The more
important projects included: equipment for Atomic-Physics Observatory;

DEPARTMENT OF TERRESTRIAL MAGNETISM 289

ionospheric apparatus; electromagnetic standard instrument; improvements
and repairs to shop; packing; and exhibit. Close collaboration was main-
tained with the various investigators that their problems might be met
effectively in the construction of instruments and equipment.

In the Atomic-Physics Observatory a heating system was installed; this
necessitated special venting and cut-off valves for use when the tank is
in operation under pressure. A water-supply system was installed, together
with a spray-system on top of the tank for cooling purposes. Gas and
compressed-air lines were extended from the main building with push-button
station-controls and pilot-lights for the latter. The necessary electric power
and lighting circuits for both direct current and alternating current were in-
stalled with suitable remote controls.

The second automatic multifrequency ionospheric equipment was com-
pleted for Watheroo. The unit for the Huancayo Magnetic Observatory
was shipped and also the one for Watheroo Magnetic Observatory after
calibration at Kensington.

Good progress was made on the electromagnetic standard instrument for
measuring the Earth's magnetic field; the grinding and lapping of the pyrex
cylinder were completed. The coil was wound after developing a satisfactory
method of lubrication and wire drawing to give the best wire surface and
proper winding tension. After winding, the coil was marked precisely by
markings in both horizontal and vertical directions for measurements of final
pitch and diameter. A special micrometer with direct reading of one micron
for measuring this coil was constructed.

A new rotating mount and shield for electromagnetic measurement of core-
samples (after design of Johnson and McNish) were constructed and added
to the pier in the Standardizing Magnetic Observatory for electromagnetic
measurements. A non-magnetic saw-table with diamond-charged copper saw
was built to cut unit-blocks from core-samples and varves for these magnetic
measurements.

Miscellaneous items included: a detector-unit and a four-stage amplifier-
unit constructed for use at Mount Wilson Observatory by Dr. Wright in
investigations of the Moon Committee ; adaptation of a 10-second circle and
verniers for gravity-apparatus by Dr. Wright of the Geophysical Labora-
tory; three contact rollers and two spare shafts for the calibrating drum of
the conductivity-apparatus at Tucson Observatory; amber insulator and
clock contactor for potential-gradient apparatus at Apia Observatory ; three
idler film sprockets and film-guard plates for light-slit of Millikan-Neher
cosmic-ray meters; a special alternating-current demagnetizing device for
use in making astatic the newly designed galvanometer magnet-systems of
Alnico; repairs and improvements to instruments and equipment for field,
laboratory, and observatory; improvements and repairs to buildings and
site ; packing and forwarding equipment, appurtenances, and supplies.

Steiner prepared an article on the method of producing nonmagnetic cast-
ings developed by the Department. This is an important subject since in the
manufacture of instruments for making magnetic measurements it is essential
that the susceptibility of all materials entering into their construction be
negligible. Castings of such materials are difficult to obtain commercially,

290 CARNEGIE INSTITUTION" OF WASHINGTON

for which reason the method of producing sound nonmagnetic castings of
copper, bronze, brass, and aluminum was developed in the Department. This
procedure has been accomplished by a close control of the melting tempera-
tures, method of purification of the material, and design of the patterns.

MISCELLANEOUS ACTIVITIES

Communications to scientific organizations and universities. Bartels gave
weekly lectures at the University of Berlin on "Terrestrial magnetism, earth-
currents, and aurora," on "Spherical harmonics in geophysics," and on "Sun-
spots and their terrestrial effects." Talks were given on "New results about
the ionosphere" and "Barometer-readings at fixed hours as material for the
computation of lunar atmospheric tides" at the University of Berlin, on
"Methods for detecting hidden periodicities in geophysics" at the Dresden
Technische Hochschule, and on "Terrestrial-magnetic inferences about solar
activity" before the Astrophysical Colloquium at Berlin-Babelsberg. Bartels
spent two weeks in October with Chapman preparing manuscript of a text-
book entitled "Geomagnetism," of which they are coauthors. Forbush pre-
sented a series of six lectures in a course at the National Bureau of Standards
on Fourier series in statistical treatment of periodicities.

Active part was taken by members of the staff in meetings of American
scientific societies through papers and discussions as indicated below or in
the report above. The Department was represented by seven papers in the
annual meetings of the American Geophysical Union in April. Fleming and
Capello prepared for publication the Transactions of the nineteenth annual
meeting of that Union (two volumes containing 745 pages). Fleming pre-
sented a paper on "Terrestrial magnetism and oceanic structure" in a
symposium sponsored by the Union upon the invitation of the American
Philosophical Society at Philadelphia in November 1937. He also attended
the round-table discussion of that Society in February 1938 on possible
economies in conventional and newer methods of scholarly publication, and
submitted a "Memorandum on planographic publication from typescript."
McNish and Johnston presented a paper at a joint meeting of the American
Section of the International Scientific Radio Union and the Institute of Radio
Engineers in April 1938 on "The American magnetic character-figure Ca in
relation to communication problems." McNish took part as guest-scientist
in a radio broadcast May 20, 1938, on "Sunspots and citizens" in the series
"Adventures in science" sponsored by the Columbia Broadcasting Company
and Science Service. Wait addressed the Engineers' Club of Baltimore in
November 1937 on "What about the ions in the atmosphere?"

Several members of the Department's staff contributed or were coauthors
in eight of thirteen chapters prepared for volume VIII of the National Re-
search Council's series "Physics of the Earth" entitled "Terrestrial magne-
tism and electricity," manuscript for which was submitted June 30, 1938, by
Fleming as Chairman of the Special Subsidiary Committee. These were:
"The Earth's magnetism and magnetic surveys"; "Magnetic instruments";
"Atmospheric electricity"; "Instruments used in observations of atmospheric
electricity"; "Earth-currents"; "On causes of the Earth's magnetism and its

DEPARTMENT OF TERRESTRIAL MAGNETISM 291

changes"; "Some problems of terrestrial magnetism and electricity"; "Radio
exploration of the Earth's outer atmosphere"; "Bibliographical notes and
selected references."

Conferences and contacts. Gish attended a conference of geologists and
geophysicists at Red Lodge, Montana, July 29-30, 1937. He also partici-
pated in the Big Horn Basin-Yellowstone Valley Tectonics Field Confer-
ence at Red Lodge, August 3-5, 1937.

Creation of a Planning and Project Committee of the American Geo-
physical Union during the past year has given opportunity for promotion of
a number of projects which rightly involve the cooperation of a number
of institutions and organizations, in which several of the Department's staff
took part.

McNish spent three weeks during July 1937 studying solar phenomena at
the Mount Wilson Observatory and conferring with members of the staff on
relations between solar phenomena and terrestrial magnetism and on pos-
sibilities of closer cooperation between investigators in these fields. He
spoke at one of the Observatory's staff-meetings on such relations. He also
discussed with Dr. Beno Gutenberg of the Seismological Laboratory in Pasa-
dena the state and constitution of the Earth's interior, and with Drs. Brad-
bury and Terman at Stanford University processes of ionization and recom-
bination in the ionosphere.

Fleming represented the Institution at the inauguration of Dr. Levering
Tyson as President of Muhlenberg College in Allentown, Pennsylvania,
October 1 and 2, 1937.

In response to a request from Dr. Jan Blaton, Director of the Meteorologi-
cal Service of Poland, Gish and Sherman provided drawings and descrip-
tions, in greater detail than has been published, of the apparatus employed
for the registration of air-conductivity on the flight of the stratosphere-
balloon Explorer II. Later Dr. Boleslaw Cynk, Assistant Chief of the
Marine Observatory, Gdynia, Poland, who arrived at the Department on
June 18 for a stay of three months, was introduced to the methods and tech-
nique of atmospheric-electric measurements by Gish and Sherman.

Detailed earth-current data covering a number of violently disturbed
periods early in 1927 were prepared by Rooney and forwarded to the Aus-
tralian Ministry of Posts and Telegraph for use in their investigation of the
connection between their operating difficulties and terrestrial electromagnetic
disturbances.

Electrical prospecting methods were discussed with a number of visitors,
particularly with Messrs. Du Houx and De Magne of the University of
Brussels, Belgium, who were interested in the apparatus and technique for
making earth-resistivity surveys.

A recorder and accessories were lent to Professor Charles M. Heck of the
Physics Department, North Carolina State College of Agriculture and En-
gineering, University of North Carolina, Raleigh, for use in research on earth-
radiation at night.

Suggestions and comments on proposed establishment of departments of
geophysics were made on request to the Department of Physics of the State

292 CARNEGIE INSTITUTION OF WASHINGTON

University of Iowa and to the Department of Geology of the University of
Virginia.

Staff -meetings and colloquia. Afternoon biweekly staff-meetings were
held from November 1937 to April 1938. These meetings were devoted to
reports on recent progress in topics bearing on problems of the Department
by members of the staff and by invited guests.

A seminar on "The propagation of radio waves in the ionosphere," in charge
of Dr. H. G. Booker, was held every Thursday evening beginning October
14, for ten meetings.

Members of the staff took part in the staff-meetings of the National Bu-
reau of Standards and the meetings of the Washington Physics Colloquium
at George Washington University.

Exhibit. Recent investigations of the radio and magnetic effects produced
by eruptions in the solar chromosphere formed the basis for the Department's
contribution to the annual exhibit of the Institution held in December. Ap-
propriate devices showed in successive steps (1) the outburst of a solar erup-
tion, (2) the cessation of radio reflections from the ionosphere, and (3) sud-
den displacement of the compass. A series of transparencies showed the in-
terpretation of the effects and the relation of the investigation to particular
problems in terrestrial magnetism. McNish and Torreson took part with
Nicholson of Mount Wilson Observatory in presenting a radio broadcast
over the Columbia network December 11, 1937, relating to the exhibit on
"Sunspots, radio, and magnetism." McNish also lectured during the exhibit
on "The Earth's atmosphere responds." Following the exhibition in Wash-
ington the Department's exhibit was shown in the Museum of Arts and
Sciences in Baltimore and in the Museum of Science and Industry in New
York.

Institution activities. Members of the staff took active part in special
committees of the Institution on physical sciences, coordination of cosmic-
ray investigations, building, lectures, exhibit, radio, application of results in
the physical sciences, and Central American volcanological investigations.

William Shepherd of the Division of Historical Research was instructed
by mail in astronomical and magnetic observations, and radio equipment for
his work in Guatemala was overhauled; his results for astronomical posi-
tion were revised. Data regarding positions of three of the Division's sta-
tions in Guatemala were supplied the Fairchild Aerial Surveys for use in the
aerial contract of the Division.

Library. During the report-year, the library has continued to acquire
copies of all new publications dealing with terrestrial magnetism and elec-
tricity, as well as publications relating to investigations in other fields con-
ducted by the Department. Accessions to the library during the report-year
numbered 610, bringing the total number of accessioned books and pamphlets
to 24,755. The practice was continued of carding, classifying, and riling in
the index all important articles of interest in current scientific journals, of
which about 100 are regularly received; hence the new accessions represent
only a small percentage of the total additions to our index, which becomes
each year progressively more valuable for reference-purposes. An outstand-
ing addition to our library is the recently acquired complete set of the Bei-

DEPARTMENT OF TERRESTRIAL MAGNETISM 293

blatter zu den Annalen der Physik und Chemie from its beginning in 1877 to
1911, thus completing the Department's set. Accordingly the last quarter
of the last century, for which no abstract-references were available in our
library, is now covered by this useful publication.

Librarian Harradon continued to take part in editing contributions to the
Journal of Terrestrial Magnetism and Atmospheric Electricity, particularly
the manuscripts in foreign languages. Notes of current interest and abstracts
of publications were prepared as well as the quarterly annotated lists of
recent publications which appear in each number of the Journal. Transla-
tions of letters and documents were made as necessary ; many of these per-
tained to international scientific organizations. Help was given in prepara-
tion of the preliminary program of the seventh triennial assembly of the In-
ternational Union of Geodesy and Geophysics.

A list of papers by the members of the Department's staff compiled by the
librarian for 1937 shows that the total number of such publications on De-
cember 31, 1937, was 1694. Separates of papers were distributed regularly
to institutions and individuals on the Department's mailing list. The service
of the International Exchange of the Smithsonian Institution was again
utilized, effecting considerable economy as on previous occasions.

Dove continued in charge of the general files of the Department, typed
many reports and manuscripts, and cared for storage and distribution of the
departmental reprints.

As heretofore, the facilities of the library were extended to investigators
and students from various institutions and governmental bureaus. Inter-
library loans were made with other libraries and cordial and reciprocal
relations were maintained, particularly with the Library of Congress, to
the mutual advantage of all concerned.

Office administration. M. B. Smith, administrative assistant, with the
assistance of Moats and Singer, looked after the numerous details of ac-
counts, audits, reports, and correspondence. Capello, secretary and prop-
erty clerk, had charge of shipments and inventory and prepared many manu-
scripts. Numerous charts, drawings, and sketches required for papers, lan-
tern-slides, and exhibits were prepared by Hendrix. Photographic work to
show development of equipment and apparatus and details of construction
was done by Ledig, who also solved a number of photographic problems aris-
ing in instrumental design.

ANTHROPOLOGY

Aberle, Sophie D., United Pueblos Agency, Albuquerque, New Mexico.
Studies of the growth and development of Pueblo Indian children. (For
previous reports see Year Books Nos. 34, 36.)

These studies, which were begun by Dr. Aberle a few years ago, have
been continued with aid from the Carnegie Corporation of New York. Addi-
tional studies have been undertaken in cooperation with the research program
of the Carnegie Institution of Washington and activities of the United States
Office of Indian Affairs and other agencies.

The two major lines of activity which have been followed throughout
the past year are analysis of the current demographic records of the Pueblo
area, by Dr. Jack Watkins of the Department of Public Health of Yale Uni-
versity, and analysis of the detailed anthropological measurements col-
lected during the past six years by Elizabeth Pitney.

Population and Vital Statistics

Vital history of San Juan Pueblo — To the analysis of the San Juan Parish
records has been added a chapter on present-day mortality in San Juan
which includes a complete life table and permits comparison with white and
Negro mortality.

Vital statistics of the pueblos — An analysis of the demography of the
pueblos as a whole is now under way. Tables showing trends of mortality
and natality, sex and age differences, and population composition are being
prepared. This information will throw light on the rate of increase in the
Pueblo population.

Dimensional Growth and Development

Detailed anthropometric measurements — The accumulation of complete
records, embodying some 50 measurements upon the same group of 200
Pueblo and Hopi children, 11 to 15 years old, was continued this year with
the addition of the sixth annual series of measurements. It was possible to
take the measurements this summer after the close of school through the
cooperation of the Indian Service, which provided transportation and the
assistance of day school teachers necessary for bringing the children to
central points for examination.

Statistical analysis of heights and weights — The analysis of the 3000
measurements of children 6 to 16 years old begun at the University of Minne-
sota has been continued at Yale. Two main objects have been pursued:
the discovery of a reliable and sensitive method for determining rate of
growth and the finding of a device for discovering possible differences in
dimensional size among children from different pueblos.

For the purpose of determining the rate of growth at different age periods
and the age at onset of the prepubertal spurt in growth, actual annual gains
in height and weight have been computed from all available repeated
measurements. It has been shown with long-time serial data that the

295

296 CARNEGIE INSTITUTION OF WASHINGTON

annual gains determine the rate of growth with greater statistical reliability
than the differencing of annual successive means of height and weight.

In addition, the test of goodness of fit has been applied to the dimensional
size of children in each separate pueblo group and these results compared to
the distribution in the group as a whole.

ASTRONOMY

Boss, Benjamin, Harry Raymond, and Isabella Lange, Dudley Observ-
atory, Albany, New York. Special studies based upon utilization and
interpretation of materials in the General Catalogue oj Stars.

During the past year the material contained in the General Catalogue
has undergone several processes in preparation for research growing out of it,
and four investigations have been completed. The first constitutes a dis-
cussion of solar motion, precessional corrections, and galactic rotation by
Ralph E. Wilson and Harry Raymond. In their treatment of the subject
solutions were made of the material arranged according to magnitude,
amount of proper motion, and spectral type in order to determine their
effects upon the problem. The constants of galactic rotation were found to
be — 0725 ± 0703 for B/4.74 and +0726 for A/4.74. The precessional cor-
rections were Ap = +0794 ±07044 and — Ae — AX = —1710 ±07045, cen-
tennial, indicating corrections to Newcomb's tables of precession in right
ascension —0-016 +0*025 sin a tan 5, and in declination +0738 cos a. The
question of solar motion has always presented difficulties. The General
Catalogue proper motions indicate a change in the position of the apex
amounting to about 4° northward per unit change in visual magnitude, as
fainter stars are employed for the solution. There are also pronounced
differences between groupings according to spectral type. The causes of
these discrepancies will be sought in a later investigation, but it is evident
that the proportion in which large skew velocities are included must be a
contributing factor.

Mr. Raymond has extended the discussion to the General Catalogue stars
with centennial proper motions exceeding 40", in two groups, proper motions
from 40" to 80", and over 80". The size of the solar motion appears to
increase very nearly in proportion to the mean proper motion of the stars
used to determine it, strongly suggesting that these stars appear to move fast
because they are near rather than because of large real velocities. There is
no northward trend of the apex, but instead an eastward trend as proper
motions increase. This amounts to 18° between the extreme groups, those
with motions less than 10r', and those exceeding 80".

In order to establish a criterion whereby parallaxes might be determined
for those stars in the General Catalogue for which no trigonometric or spec-
troscopic parallaxes have been published, a system of hypothetical absolute
magnitudes has been formed by Benjamin Boss, utilizing H and its adjust-
ment to M. In the process of adjusting, an attempt has been made to correct
for the skew distribution of the absolute magnitudes in the groups treated.
The hypothetical absolute magnitudes appear to compare favorably with
those determined from observation. Thus reasonably accurate parallaxes
are available for some 25,000 stars to add to the 8,000 previously determined.

Stellar luminosities are an important part in many astronomical investi-
gations. Consequently luminosity curves have been constructed by Benja-
min Boss and Miss Isabelle Lange for all the stars contained in the General
Catalogue utilizing the H function as the unit of luminosity and treating the

297

298 CARNEGIE INSTITUTION OF WASHINGTON

material by Harvard spectral types. The resulting curves show rather
definitely that among the stars of the General Catalogue there are but two
significant luminosity distributions, corresponding to main and giant se-
quence stars. There was absolutely no evidence of the so-called intermediate
class, whose supposed existence was apparently due to the distribution of
accidental error in observed parallaxes. Even F-type stars which have
previously offered difficulties are well represented by a single distribution.
There is however some slight evidence of a supergiant system in the case of
KO stars, but the lack of any trace of such a class in adjoining types casts
some doubt upon its reality. There is likewise a possible trace of supergiants
among the F-type stars, but if real their numbers are relatively insignificant.
The known existence of a white dwarf class among stars fainter than those
included in the General Catalogue demonstrates that we should be cautious
about closing the door to other possible luminosity distributions.

Roy, A. J., Dudley Observatory, Albany, New York. Completion of reduc-
ductions of observations of the late A. S. Flint of Washburn Observatory,
comprising the Madison Catalogue of 2786 stars, in cooperation with
Joel Stebbins, Research Associate.

Shortly after the appearance of the Boss Preliminary General Catalogue,
published by the Carnegie Institution of Washington in 1910, a cooperative
arrangement was made between the Dudley and Washburn observatories to
observe certain fainter stars for which modern positions were needed for the
Boss General Catalogue. The Dudley work was carried through and
published in the Albany Catalogue but the reductions of the Washburn
observations made by Albert S. Flint from 1912 to 1919 were not finished
at the time of his death in 1923. The completion of these reductions was
undertaken by the Department of Meridian Astrometry of the Carnegie
Institution, but for various reasons it was found that the inclusion of the
Madison results would have unduly delayed the General Catalogue.

Inasmuch as considerable progress had been made on the Washburn
material under the direction of Arthur J. Roy, the task was assigned to him
for post-retirement service to complete and prepare for publication. He
has devoted full time to this project from February 1936 to August 1938.
In addition considerable routine computing was done by students at the
Washburn Observatory under the supervision of C. M. Huffer.

There were 9900 observations of 2786 stars. The internal agreement of
the measures is testimony of the scrupulous care and skill of Flint's work.
The accuracy of the results puts this catalogue among the leading ones in
quality and it forms a valuable supplement to the larger General Catalogue.
The manuscript of 24 typed sheets of text and 56 pages of tables of the
catalogue is complete and awaits approval and editing for the printer.

BIOLOGY

Castle, W. E., University of California, Berkeley, California. Continuation
of experimental studies of heredity in small mammals. (For previous
reports see Year Books Nos. 3-36.)

The research projects initiated in the fall of 1936 under the joint auspices
of the Carnegie Institution of Washington and the University of California
have as yet been completed in one case only, that which involves the
relation to body size of the gene mutation for albinism in the house mouse.
This investigation was well advanced at the time of the last report and has
since been completed and its results published. It was found that albino
and colored mice, of identical parentage and genetic constitution except
for the difference in color, do not differ in body size, as estimated either by
body weight, body length, or tail length. The evidence is based on a back-
cross population of 1252 mice reared to the age of six months, in which
colored and albino individuals are about equally represented but do not
differ significantly in body size.

Similar investigations are in progress to ascertain whether the mutations
pink-eye2 (of Roberts), leaden, and yellow exert any influence on growth
processes so as to affect general body size. Although these experiments are
still incomplete, it appears that the mutation p2 like ordinary pink eye
(Pi), which was previously investigated, exercises a retarding influence on
body growth. Although these two mutations are genetically distinct and are
borne in different chromosomes, they seem to have a like effect on general
body growth as well as on the development of coat pigmentation. The yellow
mutation, which has long been known to be lethal when homozygous and
to result in adiposity when heterozygous, apparently increases body growth
so that adult yellow mice are considerably larger and longer-bodied than
their non-yellow litter mates.

Experiments on genetic linkage in the Norway rat have been continued
in cooperation with Dr. Helen Dean King of the Wistar Institute. We
have been able to obtain for study two useful new gene mutations of the rat
known as "wobbly" and "anemic". A foundation stock of wobbly was
kindly sent to us by its discoverer, Professor Amy L. Daniels of the Uni-
versity of Iowa. "Wobbly" rats have a lack of muscular coordination
said to resemble the "Parkinson syndrome". The character is inherited as
a simple recessive. It affects body growth unfavorably so that wobbly
individuals are usually smaller than their normal litter mates at the time
of weaning and subsequently. The animals of both sexes are fertile, but
females make poor mothers.

The mutation "anemic" was discovered by Dr. Ralph Bogart of Cornell
University, who has kindly supplied us with a foundation stock of animals
carrying this defect, which is a simple recessive and lethal character.
Homozygous anemics are deficient in hemoglobin and jaundiced in ap-
pearance and die usually at an age of 10-20 days.

A full program of crosses is in progress to test the linkage relations of
these new genes with each other and with the other known genes of rats.

299

300 CARNEGIE INSTITUTION OF WASHINGTON

The rabbit experiments are progressing satisfactorily but less rapidly than
the experiments with mice and rats because of the slower maturity of
rabbits. These experiments are being conducted in cooperation with Dr.
P. B. Sawin of Brown University. They are concerned chiefly with in-
vestigations of genetic linkage, the program of study, which is now well
advanced, covering the linkage relations of all available known genes of the
domestic rabbit. Dr. Sawin has indications of the existence of two previously
unknown linkages and these are now being subjected to intensive study,
the results of which it is undesirable to announce prior to full verification
or disproof of the indicated linkages.

Conger, Paul, Washington, District of Columbia. Continuation of investi-
gations and preparation for publication of results of studies on Diato-
macece. (For previous reports see Year Books Nos. 18-36.)

Studies during the year included a cooperative experimentation and
examination of samples in an attempt to devise more efficient methods for
separation and grading of constituent particles of diatomaceous earths for
certain industrial uses.

Facilities of the laboratory were greatly improved by the installation
of a fine new soapstone chemical-fume hood, to replace the former wooden
one. This replacement was taken care of by the National Museum, com-
pleting their program of renovation of the laboratory undertaken a couple
of years ago.

Research and field work on diatoms were carried on at the Chesapeake
Biological Laboratory for six weeks during the early part of the summer of
1937, at which time also a course on diatoms, given during several previous
summers, was again given, to a group of seven graduate students special-
izing in the fields of botany and oceanography. Additional material was
obtained toward a survey of the flora of this region.

Following this a month was spent at the Trout Lake Biological Labora-
tory of the University of Wisconsin in the lake region of northern Wisconsin,
where several hundred samples of diatom material were gathered from
approximately forty different lakes and bogs. In addition collections were
made at sixteen marl lakes near Waupaca in the east central part of the
state. Opportunity was afforded amply to confirm the previous summer's
discovery of widespread diatomaceous sediments in the northern region of
potential commercial value, and some sixty of these were collected in quan-
tity for more complete analysis and intensive study. Such study later during
the year indicated a range of from 23 to 73 per cent diatom content in these
materials, some of them proving extensive and of immediate practical
availability. Measures have been taken to assure protection of such
interests. Further investigation showed that this discovery is applicable
to similar environments in other localities in widely scattered parts of
the country, and should hold also in similar areas throughout the world.
Equally significant and interesting from a scientific standpoint was the
associated discovery of certain facts concerning the mode of formation
of such valuable sediments. A fuller report on these findings is in course
of preparation.

BIOLOGY 301

New facts and methods of presentation brought out in a paper published
during the year as part of the supplement of the Smithsonian Annual
Report, entitled "Significance of shell structure in diatoms/' are as follows:
(1) photograph of a section of a diatom by a new method showing the
double wall structure of the shell with communicating pores; (2) photograph
of a series of reproducing diatoms including two stages showing the new
shells in the midst of the process of silicification, a thing not often seen,
usually very obscure, and not previously figured; (3) a clear pictorial
contrast of the physical properties of weight and volume between diatoma-
ceous earth and sand, both materials of the same chemical composition, but
of different structure; and (4) several new uses for the earth, or in which
the diatom structure was vital.

Another paper published during the year, entitled "Exploring the lakes
of northern Wisconsin," described the work being carried on up there and
the differences between the lakes, and illustrated the great difference in
diatom flora between hard and soft water lakes.

There was also published in the April number of the Journal of the Wash-
ington Academy of Science a rather full abstract of an illustrated talk
given before the Washington Botanical Society, entitled "The diatom, an
economic plant," emphasizing a viewpoint not heretofore considered.

The first of the above-mentioned papers from the Smithsonian Annual
Report was copied in a somewhat modified form, as a number of the
Carnegie Institution of Washington News Service Bulletin.

In addition to the projects of continued floristic and ecological studies
of Atlantic Coast and Chesapeake Bay diatoms, an intensive study (as
yet unpublished) was made of the diatoms in a series of 32 core samples
collected by Dr. W. H. Twenhofel of the University of Wisconsin in rep-
resentative areas of the bottom of Crystal Lake, Vilas County, Wisconsin.
This is a small, round lake a little over half a mile in diameter, with very
clear and very soft water. A large number of species was found, and a
number of unexpected and interesting facts derived from this study. In
a small lake like this with no drainage and with a rounded and uniform
basin it was expected that a monotony and similarity of species would be
found throughout, but such was not the case ; on the contrary, marked dif-
ferences were found in a number of the samples indicating quite localized
areas of growth in the lake bed. Nutritive substances are very sparing in
the water and a slow rate of sedimentation was suspected, confirmed by
the finding of relatively thin sediments, of which fact the diatoms appeared
a good indicator. It was possible through this study to make a number
of suggestions as to the rate of sedimentation and the conditions that
prevailed in the lake at various periods during the history of formation
of these sediments.

A talk was given on April 12, before the Natural History Society of
Maryland at Baltimore on "The story of diatoms in the Chesapeake Bay
country," and this was repeated a couple of weeks later (April 23) at the
annual meeting of the Maryland Biology Teachers' Conference.

A study was made for Dr. Chancey Juday of the University of Wisconsin
on an occurrence of dense diatom growth on wall-eye pike eggs in one of

302 CARNEGIE INSTITUTION OF WASHINGTON

the Wisconsin state fish hatcheries, which growth was responsible for the
loss of approximately 50 per cent of the eggs. The exact nature of the
cause has not yet been definitely determined, but it was thought to be
through a smothering of the eggs and inhibition of development, rather than
through puncturing and actual mechanical injury.

The considerable increase in the number of requests for diatom informa-
tion and material answered during the year indicates an appreciable growth
of interest in both the scientific and the economic aspects of the subject.

Diatom investigations were carried on at the Tortugas Laboratory of
the Carnegie Institution during part of the summer of 1938. Fluctuations
in productivity of the region were studied through daily collections of
plankton. A new species of Amphora was found, interesting not only in
the fact that it was new but also because it was unusual and of considerable
importance; and further it proved to be excellent material for certain
studies on morphology and reproduction which were carried on intensively
using this form. Studies on diatom reproduction were also carried on on
several other species well adapted to the purpose. Some investigations of
nutritive relationships and on movement in diatoms were also made. The
diatom flora of the region proved unusually good for these purposes.

Dice, Lee R., University of Michigan, Ann Arbor, Michigan. Studies of
the ecology and genetics of North American mammals. (For previous
reports see Year Books Nos. 31-36.)

Most of the summer of 1937 was spent in the Capitan and Sierra Blanca
Mountains of southern New Mexico in a study of the ecological distribution
of the several species of Peromyscus which occur there. Each species has its
own habitat preferences, but in this region as many as four species of
Peromyscus may occur together in certain of the ecological associations.
The species nasutus and truei, which are closely related taxonomically and
which are partially fertile together in the laboratory, often live in the same
situations. However, nasutus lives usually in lower and hotter habitats
than truei, and no evidence was found of interbreeding in nature between
the two species.

A preliminary reconnaissance of parts of the state of Chihuahua, Mexico,
was made in late July 1937, in company with Forrest Shreve and T. D. Mal-
lery, of the Desert Laboratory staff. The high grasslands and forests of the
Apachian biotic province in the western part of Chihuahua are in striking
contrast with the desert conditions characteristic of the Chihuahuan biotic
province in the eastern part.

Most of the new breeding stocks of Peromyscus received by the Labora-
tory of Vertebrate Genetics during the year were collected in southern New
Mexico, where the races griseus, nasutus, rowleyi, rufinus, tornillo, and truei
were secured. W. H. Burt secured a stock of P. maniculatus exiguus on San
Martin Island, Baja California. Mice carrying several new mutant charac-
ters were obtained from R. R. Huestis and from the Cranbrook Institute of
Science. Specimens prepared during the year for studies of variation
number 1755.

BIOLOGY 303

A study of nine stocks of the deer mouse, Peromyscus maniculatus, from
Arizona demonstrates considerable variation in body proportions and in
pelage color from place to place. No sharp separation into geographic races
can be made, although most of the stocks can be assigned either to the sub-
species sonoriensis or to rufinus. There is a general tendency for the pelage
color on the upper surface of the mice to be correlated with the color of the
surface soil of their habitats.

A detailed study of variation in the cactus mouse, Peromyscus ermicus,
also supports the previous conclusions of Blossom and myself that the colors
of desert rodents tend to be correlated with the soil colors of their habitats.
On desert mountains made up of pale-colored rocks the cactus mice usually
are pale in color, while on dark-colored soils the mice tend to be dark in
color. An exception to this correlation is presented by Raven Butte, which
is composed of dark-colored lava, but on which the mice are pale in color.
This small butte is, however, directly connected with the Tinajas Altas
Mountains, which are composed of pale-colored rocks. With constant inter-
breeding between the cactus mice living on Raven Butte and the pale-colored
cactus mice living on the adjacent Tinajas Altas Mountains there has been
no opportunity for the development of a dark-colored race on the butte.

A study of the social relations of the wood mouse, Peromyscus leucopus,
in southern Michigan based on the use of artificial nest boxes has been com-
pleted by A. J, Nicholson. The mice are quite unsanitary about their nests
and they desert a nest which has been occupied for a time in order to take
up residence in another location. Mothers may move even their very young
offspring to a new nest, perhaps because the old nest has become foul. In
winter a number of these mice may live together in the same nest, perhaps
for the increased warmth provided by several bodies, but in other seasons
the adult mice are mostly solitary.

Methods for securing reliable estimates of small mammal abundance were
given considerable attention during the summers of 1935 and 1937. Experi-
ments were conducted with traps set in several kinds of patterns in quadrats
of various sizes and also in lines of different lengths. As a result formulae
have been developed which, when the mammal population on an area is
distributed relatively uniformly, should give a good indication of the popu-
lation of the species studied. Quadrats of considerable size when completely
trapped out give the most reliable information about populations, but
valuable information may also be obtained by trapping a line of measured
length.

A statistical study has been made of the theoretically possible effectiveness
of adverse selection. Recessive characters respond of course much more
slowly to adverse selection than do dominant, partially dominant, or sex-
linked characters. Nevertheless, the proportion of defectives produced by a
recessive factor will theoretically be decidedly reduced by adverse selection
even when the homozygous defectives form only a very small proportion of
the population. The conclusions have a bearing on proposed programs for
the improvement of human heredity based on the segregation or sterilization
of defectives.

304 CARNEGIE INSTITUTION OF WASHINGTON

Morgan, T. H., C. B. Bridges, and Jack Schultz, California Institute of
Technology, Pasadena, California. Constitution of the germinal material
in relation to heredity. (For previous reports see Year Books Nos.
15-36.)

In 1935 maps of all the salivary chromosomes of Drosophila melanogaster
were published (Bridges, Jour. Heredity, vol. 26, pp. 60-64). Those maps
showed 3540 distinct transverse lines for the four chromosomes; but, for
analyses of greater precision, more detail was found necessary. Accordingly,
a thorough revision was undertaken, using specially selected permanent
preparations. For the X-chromosome the revision has already been pub-
lished (Bridges, Jour. Heredity, vol. 29, pp. 11-13) showing 1024 lines
instead of the 725 of the former map, and representing all lines in better
relative intensities, spacing, and characteristics. In the current year a
similar revision for the right limb of chromosome 2 has been completed,
with the assistance of Philip N. Bridges. This map shows 960 lines instead
of the 660 of the former map. The greatly increased accuracy of the two
revised maps makes it now desirable to push through without delay the
revisions of the remaining maps, namely, 2L, 3L, and 3R, meanwhile de-
ferring much of the analytical work on aberrations.

A revision of the genetic linkage maps of all four chromosomes was also
carried out last year and has been published (Bridges, Tabulce Biological, vol.
14, pt. 4, pp. 343-353). This has now been supplemented by a revision of
the descriptions of the mutant types of D. melanogaster, issued as No. 9
of the Drosophila Information Service Bulletins. No such revision had been
made since that published in 1925 in Bibliographia Genetica, volume 2, pages
215-239. Careful descriptions are given of the phenotypes of the "visibles,"
such as eye colors, body colors, wing and bristle variants. Information
is given about the special mutants such as modifiers, lethals, minutes, and
the chromosomal aberrations, especially deficiencies and translocations with
the break points and new sequences of chromosomal sections. The revised
list includes over 3000 descriptions, of which many hundred are of mutants
or aberrations not previously more than mentioned. The information given
with each mutant includes: symbol, name, finder, date of origin, chromosome
and locus, references to publications, description of mutant characteristics,
with main and secondary changes and degree of variability, interaction
effects, viability, fertility. The concluding part of each description is a
summary of the relative usefulness of the mutant and its limitations.

An interesting series of five overlapping deficiencies, all of which include
the vestigial locus, has been worked out by Bridges in collaboration with
Viola Curry, P. T. Ives, and J. C. Li. Each of these deficiencies was first
detected simply as a dominant mutation showing notchings and snippings
from the edge of the wing, much like the semi-dominance shown by some
strong vestigial allels, e.g. vg-Notched of Plough and Ives. Each of the
five was lethal when homozygous, and, when crossed to the others in all
possible combinations, gave hybrids which died in the embryonic stages.
In crosses to vestigial, which is a recessive, each of the five gave hybrids
showing vestigial in an exaggerated form; hence each of the five mutants

BIOLOGY

305

could be either a lethal allel of the vestigial locus or else a deficiency in-
cluding the vestigial locus. In wing character all were very similar, but
one showed the additional characteristic of being nearly denuded of the
hairs on the anterior part of the thorax and along the legs. This one was
called Depillate, or vg-Depillate, while the others were called vg-Beaded,
vg-Carved, vg-Incised, and vg-Snipped.

Definite evidence that they were due to deficiencies rather than being
simply extreme allels came when tests were carried out with two other
mutants. One was "scabrous," an excellent recessive rough-eye character
found by Ives and located very close to vestigial. If the locus vg is taken
as the standard 67.0, then the locus of scabrous is 0.3 to the left, or at
66.7. The other mutation was a recessive lethal, discovered by Curry. By
laborious experiments the locus of "1(2)C" was found by Curry to lie to

SCA

VGC "
VQS '

VG,C "
VGBd *

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"*"£"'.

; 1 1 J ;: .

U ^

:9.:5..:

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VG +L(2)C

Al A! IIA Al
12*45- — 9-IL—

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12-45 6 78-10-

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the right of vg by 0.1 unit, that is, at 67.1. Crosses of scabrous to each
of the five suspected deficiencies gave hybrids showing scabrous in an
exaggerated form with vgc, vgDe, vglc and vgs but not with vgBd. Similar
crosses of 1(2)C to the suspected deficiencies gave lethal hybrids in all cases.
It is considered that any dominant mutant which is lethal when homozygous
and which shows pseudo-allelism to a dissimilar, non-allelomorphic but
neighboring mutant is probably a deficiency. In the present case four of the
dominants gave pseudo-allelism to three such non-allelic genes : sea, vg, and
1(2)C. The other, vgBd, differed in that it failed to include the left-most
locus, sea, though including vg and 1(2)C. The genetic evidence is thus
conclusive that each of the five is a deficiency.

This was confirmed by a study of the salivary chromosomes. Each of
the five showed the loss of a fairly long section of bands. All the deficiencies

306 CARNEGIE INSTITUTION OF WASHINGTON

are different in the details of extent and position, but all overlap, with a
zone of bands whose loss is common to all. In figure 1 is shown the normal
banding of section 49, according to the revision just finished. The extent
of each of the deficiencies is indicated in the figure, though there is still
some uncertainty in the cases of vgs and vgDe as to the exact positions
of the breaks. The shortest deficiency is vgDe, extending from just
to the left of 49C2 to somewhere in the faint band region of 49E. This
shortest deficiency includes all three loci: sea, vg and 1(2)C. Two
others of the deficiencies have breaks within this salivary zone and serve to
narrow still more the correspondence limits. Thus, vglc has its left break at
the end of 49C just to the left of the two dark bands at the beginning of 49D.
Since vglc also includes sea, vg, and 1(2)C, these three loci must lie within
49D and the left half of 49E. The left break of vgBd is just to the right of
49D3, and since vgBd does not include sea, this break shows that sea lies
within the narrow zone of 49D1 through D3, while vg and 1(2)C lie between
49D3 and 49E5. Inspection of the salivary chromosomes of 1(2)C failed
to show any loss in the small region within which the locus must be situated.

It should be noted that since the wing effects of all five of the mutant
types are practically identical, this character can be attributed to the loss
of the vestigial locus. But the depillate character shown by one of them is
not due to simple deficiency, for in that case it should have been shown by at
least two others of the five, since all material lost by the vg-Depillate de-
ficiency is also lost in two or more of the others. Simultaneous mutation,
probably at one of the two break points, or an effect due to the new juxta-
position, must be assumed.

Study of the salivary chromosomes of vg-Snipped showed that it is two
separate deficiencies, both presumably due to the X-raying to which Muller
had subjected the parent of the vgs mutant. The other deficiency includes
the first band of 42D, which is fairly strong, and about half of the preceding
subdivision, 42C, including two readily seen bands.

There was on hand another dominant mutant called vg-eleven which also
shows wing-notching, but in addition shows smaller bristles, as in a slight
"Minute." This type is lethal when homozygous. Salivary inspection
failed to show a deficiency in the vg region. Genetic analysis then showed
that vg11 is a double mutant type, again due to X-raying (by Sturtevant and
C. Ruch). At the vg locus is an extreme, non-lethal, semi-dominant mutant
like vg-Notched of Plough. The "Minute" effect is lethal when homozygous,
is located not at vestigial but very close to Bristle, and gives pseudo-domi-
nance to straw in hybrids. Hence vg11 is a combination of a dominant
vg allel and a Minute which is a deficiency for straw.

Besides the Minute effect of vg11, three other Minutes produced by X-rays
are known which have similar location and give pseudo-dominance to straw.
These are M(S)2, M(S)4, and M(S)8. M(S)4 is also deficient for blot,
which is mapped at 55.3, while straw is at 55.1. These four Minutes are
lethal allels of each other. None shows any detected effect in the salivary
chromosomes, but since the region under suspicion is the chromocentric
portion of 2R, the normal irregularities and adhesions there may be con-
cealing the loss of bands.

BIOLOGY 307

A valuable correspondence has been established between the bands of the
salivary map and the locus dumpy, with its numerous allels, at 13.0 in 2L.
This was through a Minute found by Curry "M(2)C" which is a deficiency
for dumpy and which shows in the salivaries as the loss of the section of
bands from just to the right of the faint band in 24D to half through the
"shoe-buckle" set of four bands in 25A.

The well-known reciprocal translocation "Blond" has been reinvestigated.
It was found that the break in the X comes between 1C3 and 1C4 of the
revised map of X. To the left of this break point lie the loci: Hairy-wing,
yellow, achete, scute, lethal-7e, suppressor of sable, suppressor of black,
silver. To the right of the break are: stubarista, lethal-7, twisted, giant,
broad, kurz, prune. The break in 2R precedes the last thin line of 60B (that
is, extends to left a bit further than previously reported) . To the right of
this break lie speck, blistered, balloon; to the left lie 1(2)NS and 1(2) ax.
The above determinations of order were made by use of the viable "Blond-
Minute" derivative which is deficient for the tip of X and duplicated for
the tip of 2R, and by the reciprocal "Plexate-Minute" derivative which is a
duplication for the tip of X and a deficiency for the tip of 2R. It was also
found that Blond is superimposed on Inversion (2R) Curly, which was pre-
sumably present when T(l;2)Bld arose. Efforts to separate the trans-
location from the inversion, through crossing over in the narrow space be-
tween them, were not successful. Homozygous T(l;2)Bld females survive
with extreme rarity.

The preceding analyses of deficiencies and translocations are examples
from extensive material bearing on the general problems of chromosome
structure and on the relation between that structure and mutation on the
one hand and, on the other, the breaks which lead to aberrations or to
crossing-over. The evidence upon rearrangements points to the conclusion
that breaks, whether spontaneous or induced, come first at random points
corresponding to accumulation of strain or weakening effects. Thereafter
occurs a reassemblage of the parts by the union of each fresh end with
whichever other fresh end it encounters. The refusions seem to show that
differences in chromosomal origin of a piece, and in polarity, i.e., whether
in normal or inverted order, have no significance.

During the past year Schultz has been on leave of absence, holding an
International Fellowship of the Rockefeller Foundation, and working at the
Chemical Department of the Caroline Institute at Stockholm, Sweden, with
Dr. Torbjorn Caspersson. The following is a brief report of their joint work.

The optical methods developed by Caspersson for the measurement of
nucleic acid in the cell had already indicated a relation between the aug-
mentation of the content of this substance in the chromosomes and the
process of chromosome division. As a result of the application of these
methods to the Drosophila material, evidence has been obtained that the
nucleic acid metabolism of the chromosomes is changed in the cases of
abnormal gene reproduction which are characteristic of the variegated races
of Drosophila. These races (see the reports in Year Books Nos. 33-36)
contain chromosome rearrangements involving the heterochromatic regions
rich in nucleic acid; in certain favorable cases the study of the salivary gland

308 CARNEGIE INSTITUTION OF WASHINGTON

chromosomes had shown that the variegation is correlated with deficiencies
in the salivary bands closest to the point of rearrangement, and with a
darkening of the immediately adjacent remaining bands suggesting a change
in their nucleic acid balance. The nucleic acid content of these bands has
now been measured by a photographic method, by means of which quantities
of nucleic acid of the order of magnitude of 10 _11 mg. can be estimated.
An increase of the nucleic acid content of these bands over the normal is
present, greatest close to the heterochromatic regions, less farther away.
A similar relation to distance from the heterochromatin holds for the varie-
gation: the closer a band is to the point of breakage, the greater the extent
of variegation for that gene.

When additional heterochromatin (an extra Y-chromosome) is present in
the nucleus, the variegation is decreased in extent and the cytologically
visible deficiencies are both fewer and shorter. The bands which in the
XX female have more than the normal amount of nucleic acid, show in the
XXY female only a slight augmentation. However, the bands which were
lost in the XX female have, when present in the XXY, an increased nucleic
acid content over the normal. It may be, although the evidence is not com-
plete, that the augmentation of the nucleic acid content of a band is a stage
in the loss of that band. In any case, with the change in either the distribu-
tion or the amount of heterochromatin in the nucleus, both the concentration
and the total amount of nucleic acid on the affected bands are changed.
The nucleic acid behavior is entirely parallel to that of the genes: the
nucleic acid content of a band is dependent both on its neighbors in the
chromosome (position effect) and on the general relations in the nucleus
(genie balance).

Further evidence correlating changed nucleic acid metabolism with varie-
gation comes from the study of the egg cytoplasm, in which the cell divisions
responsible for variegation occur. During the oogenesis, there is a change
in the absorption spectrum of the cytoplasm from one like the proteins
in the oogonia, to an absorption spectrum related to that of nucleic acid
in the mature egg. There is therefore in the oogenesis of Drosophila, a
synthesis of cytoplasmic substances related to nucleic acid. That this
synthesis is related to nuclear activity (although the egg nucleus is notably
poor in nucleic acid) appears from the visible gradient of the concentration
of such substances in the cytoplasm — highest around the nuclear membrane,
and decreasing peripherally. The effect of an additional Y-chromosome
has been studied and it has been found that females containing an additional
Y-chromosome show an increase in the amount of these absorbing substances
synthesized in oogenesis. This result has been obtained in ten series of
experiments, with four different stocks of variegated Drosophilas. Since
it is known (Noujdin) that the presence of an extra Y-chromosome in the
mother decreases the extent of variegation in her XX progeny, these results
show that not only the nucleic acid metabolism of the chromosomes, but that
of the cytoplasm as well, influences the development of variegation. In
addition there is here evident an interplay of chromosomes and cytoplasm:
the Y-chromosome influences the egg cytoplasm, which in turn determines the
loss of genes in the embryonic divisions, leading to variegation of the adult.

BIOLOGY 309

The relation of these cytoplasmic absorbing substances (probably similar
to the pentose nucleotides reported by Brachet in marine eggs) to the ensu-
ing cleavages presents a problem of related interest. The distribution of
the substances in the mature egg has been studied by a special technique for
the detection of very slight differences at high absorptions. It has been
found that the concentration of these substances is greatest at the center of
the egg, where the first and most rapid divisions occur. The correlation
indicated seems, on the basis of observations of other tissues, to be a general
one. Young and actively dividing tissues have a high concentration of
absorbing substances.

The study of the growth of the salivary gland cells has furnished more
data, of a complementary nature. In the young larva (1-2, 2-3 days old)
the cytoplasm has an absorption spectrum similar to that of the substances
containing the pyrimidine ring which gives nucleic acid its characteristic
absorption. As the larva grows the absorption spectrum changes in a way
consistent with the idea that the protein content is increasing. The absorp-
tion spectrum of the mature salivary gland shows more variability, possibly
correlated with the activity of the gland at this stage. Significant is the
comparison of the total absorption of the young cell with that of the nucleus
alone in the mature cell. The total absorption of the mature nucleus may
be as much as twice that of the whole young cell. This fact indicates a
synthesis of thymonucleic acid in the salivary gland, correlated not with
preparation for mitosis, but with the growth of the chromosomes and hence
with gene reproduction. This is in agreement with Caspersson's finding that
the stage of the mitotic cycle at which the augmentation of nucleic acid
occurs is the early prophase, before the appearance of the split chromomeres.

The combined results indicate a close relation between the nucleic acid
metabolism of the cell and gene activity and reproduction. There has also
been found, on comparison of the band corresponding to the white gene with
its normal allelomorph, a decreased amount of nucleic acid as the result of
the mutation to white (see also last year's report). The extension of the
method to other mutations may prove a fruitful tool for the analysis of the
mutation process.

Considered in relation to the physico-chemical properties of thymonucleic
acid (Hammarsten), its property of forming polymers of high molecular
weight, of a long chain shape (Signer, Caspersson and Hammarsten) with
an X-ray diffraction pattern with a period corresponding to that of a fully
extended polypeptide chain (Astbury and Bell), the present results allow
more concrete speculation concerning the nature of gene reproduction. It
seems plausible to consider the process of gene reproduction as being essen-
tially the polymerization of smaller units into a large aggregate, whose sub-
sequent depolymerization causes division. Also relevant are the recent
studies of the viruses, showing as they do the occurrence of a nucleic acid in
all those adequately studied, as well as, in the case of bacteriophage, a
relation between the nucleic acid portion of the molecule and its activity
(i.e., its ability to reproduce itself). The possibility is suggested that the
synthesis of nucleic acid is characteristic for self-reproducing protein
molecules.

APPLICATION OF RESEARCH TO PROBLEMS IN

CONSERVATION

Through assistance given by the Carnegie Corporation of New York, in
cooperation with the Carnegie Institution of Washington, it has been pos-
sible to pursue studies bearing upon the formulation of policy and adminis-
trative procedure in the following conservation projects located in Cali-
fornia: (1) Point Lobos; (2) Coast redwoods; (3) Old Monterey. Newton
B. Drury, Research Associate in Study of Primitive Areas, who is represent-
ing the interests of the Institution in these projects, presents the following
report.

Point Lobos Reserve (for previous report see Year Book No. 36). Ob-
servations have been continued along lines outlined in the Point Lobos
Master Plan Report, and administrative policy has been shaped in con-
formity with principles developed in that report. Adoption of the recom-
mendation by the Advisory Committee against picnic fires or smoking in
the Reserve, together with arrangements for more thorough fire protection,
give greater assurance against destruction of perishable values through this
menace.

The State Park Commission has approved allocation of funds to acquire
the off-shore rocks from the federal government, thus assuring the protection
of remarkable wild-life exhibits presented by the pelicans, gulls, and cormo-
rants on Bird Rocks, at the south end of the Reserve, and the colonies of
California and Steller's sea lions on Seal Rocks near Cypress Headland.
Favorable comment upon the results already apparent from the policies
being pursued by the park commission at Point Lobos has been made by
Dr. Joseph Grinnell, director of the Museum of Vertebrate Zoology, Univer-
sity of California, who was one of the scientists participating in the Master
Plan Report. After a recent inspection, he wrote:

"I was intensely interested in seeing the great extent of plant succession
which has developed in the brief three-year period since I first looked at
the place closely. . . . All this seems to account for the changes also
apparent in the bird and mammal life. ... It is pleasing to see the
natural processes going on undisturbed."

Coast redwoods. Under the direct guidance of Dr. John C. Merriam,
studies of human values inherent in the redwood forests, particularly in
Humboldt Redwood Park and the Bull Creek region, have been inaugurated.
Following much the same pattern as the Point Lobos studies, the scientific
and aesthetic features of significance in these areas are being analyzed, with
a view to interpretation of the redwoods to the public and the formulation of
sound policy for the protection of these forests.

In this connection, Dr. Merriam had this to say:

"Years of observation have seemed to indicate that, while much is said
about grandeur and wonder and beauty, commonly the multitude passes
through and is interested in the wonders, but the individuals are not able
to focus attention upon particular or definite things and therefore lose much
of what might otherwise be available to them from the experience. . . .
A study of what should be selected and how it might be defined is a matter

310

CONSERVATION 311

for critical investigation by those who have exceptional vision and power of
expression."

Appointment of a special committee to cooperate with Dr. Merriam in
making these studies was authorized by the Council of the Save-the-Red-
woods League at their annual meeting in San Francisco on August 29, 1938.

Monterey state historic monuments. Recent acquisition by the state of
the Old Custom House on Monterey Bay, dating from the Mexican regime
in California, the site where Commodore Sloat in 1846 raised the American
flag and claimed the territory for the United States, has quickened interest
in the historical background of this picturesque community, in which the
state has a group of three historic monuments. Like St. Augustine, Florida,
the city of Monterey affords opportunity for historical research and pos-
sesses relics of successive cultures that should be preserved. Studies of
the Spanish, Mexican, and early American periods at Monterey have been
made by Dr. V. A. Neasham of the Bancroft Library, University of Cali-
fornia, with particular reference to over one hundred sites and structures
related to Monterey's early history. A preliminary master plan for pres-
ervation of the historic meaning and landscape beauty of Monterey in
harmony with its future development as a growing community has been
made by Mr. Emerson Knight, landscape architect and planning adviser,
and has been approved in principle by the City Planning Commission, the
Harbor Committee, and the City Council of the city of Monterey.

ECOLOGY

Elton, Charles, Oxford University, Oxford, England. Natural fluctuations
in North American animal populations.

The grant made by the Carnegie Corporation of New York and adminis-
tered through the Carnegie Institution of Washington has enabled the
Bureau of Animal Population in Oxford University to maintain effectively
two important inquiries into natural fluctuations in North American animal
populations. These inquiries have been carried out by the aid of various
administrative and scientific organizations in Canada and the United States,
the details being available in the published reports (see bibliography).

The Snowshoe Rabbit Enquiry is a questionnaire inquiry to field men
which is mapped by objective methods at Oxford, and gives a year-to-year
record of fluctuations in this rodent, which cover a huge area — practically
the whole of the northern forest zone of Canada and the eastern United
States. The cycle has a period of about ten years, and the very widespread
action of it simultaneously in different regions suggests the possibility of
a relation with climatic rhythms.

The Canadian Arctic Wild Life Enquiry is concerned with a similar
fluctuation in lemmings, arctic foxes, and other arctic animals, which have,
at any rate in the eastern Arctic, a marked cycle of about four years,
covering also a very large area. The main part of the work at Oxford
has been carried out by Mr. D. H. Chitty, who has received part of his
salary from the grant, the rest of which has covered the expenses of mate-
rials, maps, photography, etc., and the coordination of other materials
concerned with these cycles. The work has been supervised closely by the
Director, Mr. Charles Elton, who carried on the inquiries in previous years.

The Canadian Artie Wild Life Enquiry for 1936-1937 (mapped in 1938)
will be published in the Journal of Animal Ecology in November 1938.
The report for the previous year (see bibliography) explains the scope
of its organization. The Snowshoe Rabbit Report for 1936-1937 (mapped
in 1937-1938) was published in the Canadian Field-Naturalist.

These inquiries are providing abundant material for recording and ana-
lyzing these two important population rhythms, but it is desirable to con-
tinue them for a number of years to get a full story of their action.

The Snowshoe Rabbit Enquiry is now being linked with a five-year plan
of quantitative recording of snowshoe rabbit reproductive rates at five
Hudson's Bay Company posts in the North.

312

EMBRYOLOGY

Hertig, Arthur T., Boston Lying-in Hospital, Boston, Massachusetts. Re-
search in embryological pathology. (For previous report see Year
Book No. 36.)

This report concerns progress of studies on early hydatid degeneration in
the human placenta originally undertaken by Dr. Arthur T. Hertig at the
Boston Lying-in Hospital in 1936. These studies have been carried on dur-
ing the past year by Benjamin Kropp, Ph.D., under Dr. Hertig's general
direction with continued financial support of the Carnegie Corporation of
New York, and collaboration of Dr. G. L. Streeter, Director of the Depart-
ment of Embryology of the Carnegie Institution of Washington.

For purposes of experimental approach the work may be regarded as
falling into two very general categories: (1) the relationship of angiogenesis
and of blood vessel structure to early hydatid degeneration, and (2) the
growth and structure of trophoblast and early trophoblastic derivatives in
relation to early hydatid degeneration.

The detailed histo-pathological studies of abortuses which are the seat of
hydatid degeneration have been continued. The material at hand, and
constantly being added to by the pathological laboratory at the Boston
Lying-in Hospital, is very extensive, and will involve much more study.
Attention is being focused primarily at present on the vascular patterns of
the placenta, although it is borne in mind that the material is also important
for studies on epithelial structures. Certain vascular conditions involving
endothelial structure, capillary form and location, as well as histological
anomalies of erythroblasts, have been consistently encountered and observa-
tions along this line are being continued.

It was found desirable to verify on material available locally certain con-
clusions reached by Dr. Hertig in his studies on angiogenesis in the human
chorion. To this end, using material of the Minot Embryological Collection
in the Harvard Medical School, reconstructions of portions of the immature
placenta were made, including chorion, primary and secondary villi, and their
developing vascular patterns. Histological observations and reconstructions
showed the presence of discontinuous capillary buds in all these structures
as well as the presence of modified trophoblastic cells, angiogenic in nature,
as described by Dr. Hertig.

The mineral content of the human fetal membrane in various stages is
being studied by the microincineration method. A preliminary report of
the results of this study on the mature amnion and chorion was delivered
at the Pittsburgh meeting of the American Association of Anatomists in
April 1938. A more extended statement of the results of this investigation
is in preparation for publication. While it is believed that the use of this
method may be fruitful, the practical difficulty of obtaining fresh material
which is the seat of early hydatid degeneration may limit its usefulness to
more advanced stages of hydatid degeneration.

An approach to the problem of hydatid degeneration which it is hoped will
be productive deals with the factors involved in the early growth and
differentiation of trophoblast, since pathological changes in hydatid degenera-

313

314 CARNEGIE INSTITUTION OF WASHINGTON

tion involve the trophoblastic derivatives so extensively. The method
adopted is that of transplanting to the anterior chamber of the rat eye
young rat ova at a stage when the trophoblast is highly proliferative. In
the experiments performed practical difficulties were encountered in the
operation and the maintenance of the graft. These difficulties have, for the
most part, been overcome. While results are thus far scanty and incon-
clusive, the results are sufficient to show that the method should be developed
and further experiments are planned.

Schultz, Adolph H., Johns Hopkins Medical School, Baltimore, Maryland.
Researches on Asiatic primates.

The man-like apes of Asia have been much less intensively studied and
are less well represented in our collections than are those of Africa, yet
they are of greatest importance for the full understanding of man as a
primate. In order to gain new information on and more material of Asiatic
primates the writer joined Mr. H. J. Coolidge, Jr., a primate taxonomist
of Harvard University, and Dr. R. C. Carpenter, a psychologist of Colum-
bia University, in an Asiatic Primate Expedition which lasted from early
in January to late in September of 1937. The writer's participation was
made possible through a financial contribution from the Carnegie Institution
of Washington, received by special grant from the Carnegie Corporation
of New York. In all his field work the writer was very ably assisted by
Mr. S. L. Washburn, a graduate student in anthropology of Harvard
University.

The expedition's work was carried out chiefly in northern Siam, British
North Borneo, and Sumatra. Approximately 400 primates were collected,
consisting of mainly the following species: orang-utan, gibbon {Hylobates
lar and H. cinereus), proboscis monkey, langurs (Pygathrix pyrrhus, P.
cristatus, and P. rubicundus) , macaques (Macaca assamensis, M. irus, and
M. nemestrinus) , and slow loris {Nycticebus borneanus and N. bengalensis) .
In addition a series of three shrews was obtained which is of special interest
to primatologists.

All these specimens were thoroughly examined in the field. They were
first weighed and measured in detail, many were photographed, of some
plaster casts were made, notes and sketches were gathered of most outer
features, of the movability in certain joints, of the occlusion of the teeth,
the condition of the mammary glands, etc. Every specimen was then
skinned and autopsied. All female reproductive tracts and all embryos
and fetuses were carefully preserved for later laboratory study. Internal
parasites and samples of stomach contents were saved for identification
and analysis ; various organs were measured in the field and others preserved
for study by specialists at home. Diseased and anomalous conditions were
fully recorded or, in many instances, preserved, and, finally, the skeleton
was prepared for shipment after certain spinal measurements had been
taken on the freshly eviscerated body. Together with the hunting and
observing of living apes these activities filled every available moment in
the field and provided a mass of new data and of valuable material for at
least several years of profitable study in the laboratory.

EMBRYOLOGY 315

On his way home the writer spent eleven days at the Raffles Museum
in Singapore, examining the extensive collections of gibbon, siamang, and
orang-utan skulls, generously placed at his disposal by the director, Dr.
F. N. Chasen. These additional data will be of greatest help in the statis-
tical analysis of age changes, sex differences, degrees of variability, fre-
quency of anomalies, etc., in these apes.

Since his return the writer has spent all his efforts in the preparation
and study of the enormous material collected and in tabulating and ana-
lyzing the manifold and extensive field data, preparing them for later
publication.

It is confidently expected that the completed work on this expedition
will result in new and much-needed information on the developmental
changes, the variability, the sex differences, the evolutionary adaptations,
etc., in Asiatic primates, which, in turn, will help greatly to elucidate the
general primate characters as well as the newly acquired peculiarities of
man. So far it has been possible to complete only a few minor studies (see
bibliography) . In one paper it was shown that, contrary to previous claims,
marked swelling of the genital region occurs in orang-utans, as it does in
the African great apes, but in the former apparently only during pregnancy
rather than during the menstrual cycle, as in the latter.

Another paper deals with the relative length of the various regions of
the intact spinal column and demonstrates for the first time that all the
higher primates differ from the lower catarrhines in possessing relatively
much longer cervical and sacral regions, slightly longer thoracic region,
and much shorter lumbar region. Man differs from the anthropoid apes
in having the longest cervical, thoracic, and lumbar regions. In all the
primates studied males differ from females in having the relatively longer
cervical and the relatively shorter lumbar region.

In a third paper it is shown that in relation to the general body weight
the testes of macaques are approximately twelve times heavier than those
of langurs. The percentage relation averages in the former about 0.74,
whereas in the latter it is only about 0.06. The corresponding approximate
average is 0.08 for gibbons, 0.05 for orang-utans, 0.27 for chimpanzees, and
0.08 for man. The unequaled relative size of the testes in macaques is
rendered even more remarkable by the finding that there is a greater pro-
portion of sex-cell producing glandular tissue in the testes of macaques than
in those of, for example, langurs.

Of further results can merely be mentioned so far that wild gibbons
show an astoundingly high rate of old, healed fractures of chiefly the limb
bones, all adults are heavily infected with Filaria, diseases of the joints
are very common, and atrophy of one limb, cystic enlargement of ovaries,
umbilical hernia, cryptorchism, etc., could be recorded in a very consider-
able number of cases. Anomalous formations were found in wild gibbons
with surprising frequency and diversity, particularly Polydactyly, bra-
chydactyly, syndactyly, spina bifida, supernumerary nipples and teeth,
forking of ribs, 8 or only 6 cervical vertebrae, fusion of atlas with occiput,
etc. All this in a population of man-like apes in their natural environment
gives a picture to cast doubt on the prevalence of health and normalcy in
nature and on the efficacy of natural selection.

GENETICS

Babcock, E. B., University of California Agricultural Experiment Station,
Berkeley, California. Cytogenetic and taxonomic investigations in the
Crepidince. (For previous reports see Year Books Nos. 25-36.)

This concluding report will review briefly the principal results of these
investigations, giving references to the publications reporting these results.
Several publications which are still in preparation will also be mentioned.

The original purpose of the project was thoroughly to investigate the
genus Crepis with reference to the chromosomes of the species, the geographic
distribution of the species, the cytogenetics of interspecific hybrids, and the
bearing of these three lines of evidence on the taxonomy, phylogeny, and
evolution of the genus.

The last published report on the chromosomes of Crepis is that of Babcock
and Cameron1 which treats of 108 species. At least 13 additional species
have been acquired and examined and these, together with a revised list of
all the species studied cytologically, will be reported in a forthcoming paper.
In the genus as at present delimited (excluding Youngia, Glomeratce, Dubycea,
and Mtheorrhiza) the following diploid numbers occur: 6, 8, 10, 12, 14; also
among the Old World group there are several tetraploid species with 2n = 16
(x = 4) , two octoploid species with 2n = 40 (x = 5) , and possibly a deca-
ploid species with 2n = 40 (x = 4?) ; whereas in the native American species
(except nana and elegans with 2n = 14) only the base number 11 occurs and
the following somatic numbers are found: 22, 33, 44, 55, 66, 77, 88. This
unique situation in the native American species, as compared with the rest
of the genus, is fully discussed in relation to geographic distribution, poly-
ploidy, and apomixis in the forthcoming monograph by Babcock and Steb-
bins.2

As a supplement to the monograph of the North American species of
Crepis, the mechanism of apomixis in these species has been studied by
Stebbins and Jenkins (unpublished). In all diploid forms investigated,
meiosis is normal in both P.M.C.'s and E.M.C.'s, and there is no evidence
of apomixis. In the polyploids, a varying proportion of ovules in each form
investigated exhibits somatic apospory followed by diploid parthenogenesis.
In all the twelve forms except one (C. occidentalis, subsp. pumila apm.
hamiltonensis) there are some ovules (usually 12-22 per cent) in which
meiosis is completed and an embryo sac is formed from a megaspore with
the reduced number of chromosomes.

Meiosis in the P.M.C.'s is not remarkably irregular in the apomicts, and
the degree of pairing is high. Multivalents were found in all forms investi-
gated. In a triploid C. acuminata the P.M.C.'s degenerate in prophase, and
meiosis never begins. This degeneration is preceded by and probably
caused by the degeneration of the tapetum. In C. occidentalis apm. hamil-
tonensis a type of restitution nucleus is formed at second metaphase and
anaphase by lateral fusion of chromosome groups belonging to different
spindles.

1 Babcock and Cameron, Univ. of Calif. Publ. Agr. Sci., vol. 6, no. 11, pp. 287-324 (1934) .

2 Babcock and Stebbins, Carnegie Inst. Wash. Pub. No. 504, in press.

316

GENETICS 317

The situation in these species closely corresponds to that in Hieracium
subg. Pilosella. It explains clearly the type of variation observed in nature.
New forms, mostly hybrids, can be formed continually through fertilization
of the eggs in occasional sexual embryo sacs. These new forms are kept
constant by means of apomixis.

The geographic distribution of the Old World species of Crepis has been
discussed in "The origin of Crepis and related genera."1 The general con-
clusion regarding Crepis is that the center of origin was in southwestern
Asia, and that migration from this center occurred toward the west into
Europe and Africa, and toward the northeast throughout Asia and eventually
into western North America. In the essay just cited there was suggested
a working hypothesis concerning the phylogenetic relations between Crepis
and three large closely related genera, Hieracium, Lactuca, and Prenanthes,
based on the concept that 10 is the most primitive number of chromosomes
in this group of genera. It should be pointed out, however, that the com-
parative morphology of existing species is not wholly consistent with this
hypothesis, and that a broader survey of the chromosome numbers in the
tribe Cichorieae as a whole may necessitate the adoption of a different
hypothesis.

Cytogenetic studies on 11 interspecific hybrids, made by several different
investigators, have been reviewed recently.2 This evidence supports the
evidence from comparative morphology and geographic distribution which
indicates that Crepis, as delimited above, is a natural group of closely related
species. Although several major subgeneric groups are recognized as pro-
viding a convenient basis for systematic classification, yet the species thus
classified are more or less closely related, i.e., their genie complements are
more or less homologous. This generalization is supported by more recent
studies on groups of very closely related species3 as well as by other work
on interspecific hybrids in Crepis.4'

The bearing of all these investigations on the phylogeny and evolution of
Crepis has been summarized by Babcock and Navashin5 and Babcock and
Cameron.6 This evidence is invaluable in working out a natural taxonomic
treatment of the genus, and it is hoped that when the general monograph
is completed it will also prove of practical value for purposes of identification
and classification in this genus.

Other genera of the Crepidinse to which special attention has been given
during these investigations are Youngia;7 Prenanthes, Dubycea, Lactuca, and
Ixeris;8 Glomerate (unpublished); ^Etheorrhiza (unpublished). Further-
more, preliminary taxonomic and cytologic studies have been made in some

1 Babcock, in Essays in geobotany in honor of William Albert Setchell, pp. 9-53, Univ.
Calif. Press (1936).

2 Babcock and Emsweller, Univ. Calif. Publ. Agr. Sci., vol. 6, no. 12, pp. 325-368 (1936).

3 Jenkins, Univ. Calif. Publ. Agr. Sci., vol. 6, no. 13, in press; Babcock and Cave, Ztscbr.
ind. Abst. Vererb., vol. 75, no. 1, pp. 124-160 (1938).

4 Collins, Hollingshead, and Avery, Genetics, vol. 14, pp. 305-320 (1929); Poole, Univ.
Calif. Publ. Agr. Sci., vol. 6, no. 6, pp. 169-200 (1931) ; Hid., no. 9, pp. 231-255 (1932).

5 Babcock and Nevashin, Bibliographia Genetica, vol. 6, pp. 1-90, 1930.

6 Babcock and Cameron, op. cit.

7 Babcock and Stebbins, Carnegie Inst. Wash. Pub. No. 484, iii + 106 pp. (1937).

8 Babcock, Stebbins, and Jenkins, Cytologia, Fujii jubilee vol., pp. 188-210 (1937).

318 CARNEGIE INSTITUTION OF WASHINGTON

40 to 50 other genera mostly in other subtribes than the Crepidinse. This
survey of the whole tribe Cichoriese has been undertaken because the sub-
tribe Crepidinse as heretofore constituted can hardly be considered a natural
group of genera, whereas the Cichorieae as a whole can be so considered.
Hence there is reason to expect that this broader survey will throw consid-
erable light on the phylogenetic relations of the Crepidinse. It is hoped
eventually to publish a generic revision of the Cichoriese.

During the past year the writer has been assisted in the Crepidinse inves-
tigations by Dr. G. L. Stebbins, Jr., taxonomist and cytogeneticist ; Dr. J. A.
Jenkins, cytologist and geneticist; Mr. E. Jund, technician; Mrs. J. A. Jen-
kins, artist.

Burks, Barbara S., Eugenics Record Office, Cold Spring Harbor, Long
Island, New York. Studies of available data in connection with research
projects in the field of human heredity. (For previous report see Year
Book No. 36.)

The following report has been submitted with relation to studies under-
taken at the Eugenics Record Office by Dr. Burks through support of funds
granted by the Carnegie Corporation of New York to the Carnegie Institu-
tion of Washington.

The year was divided fairly evenly between the completion or continua-
tion of projects already under way and newly initiated projects.

Studies in linkage. During the previous year, family schedules utilized
from the Eugenics Record Office files had given indications of autosomal
linkage between congenital tooth deficiency and hair color and possibly be-
tween myopia and eye color. To check upon these results, and to clarify
points of detail, two field studies were pursued during the current year, with
propositus tooth deficiency and myopia cases located through the coopera-
tion of New York clinics.1

The tooth deficiency field study, which made use of X-ray diagnosis and
of objective appraisal of hair color and other traits, corroborated the earlier
study in the detection of linkage, in the hypothesis which best accounted
for the mode of transmission of tooth deficiency and of hair color, and in the
estimated recombination ratio (approximately 10 per cent). The material
went farther than the earlier data in permitting a formulation (through link-
age relationships) of the genetic relationship of congenitally missing third
molars and other congenitally missing teeth, which were formerly believed to
be independently inherited. The phenomenon appears to be comparable to
the irregularly selective effect of Dichsete, Hairless, Scute, or Echinus in sup-
pressing particular bristles in Drosophila. These data on autosomal linkage
in man were made the basis of a paper at the annual meeting of the Eugenics
Research Association, and an exhibit at the annual meeting of the Genetics
Society of America.

The field data on myopia, whose collection was completed toward the end
of the current year, are still in the process of analysis and interpretation.

1 Tooth deficiency cases were located through the Murry and Leonie Guggenheim Dental
Clinic and the New York University Dental Clinic; myopia cases were located through Man-
hattan Eye, Ear, Nose and Throat Hospital.

GENETICS 319

Several other pairs of traits showed indications for linkage sufficiently
promising to justify collection of further data for crucial tests of detection.
Ground work has been laid for an investigation of possible linkages between
somatic traits and a psychological disposition, cyclothymia. The New York
State Department of Mental Hygiene has promised its cooperation in locat-
ing subjects. Dr. A. S. Wiener will collaborate by determining the blood
types of subjects.

Objectivity of data. Data collected during the previous year on sets of
family schedules filled out independently by sibling pairs, and on self-ratings
compared with objective appraisals of certain physical traits, have been sub-
jected to statistical analysis. One paper on this problem is ready for publi-
cation ; another will soon be completed. The results indicate that the traits
included in the available family schedules vary in the objectivity with which
respondents are able to record them, and that a single trait may vary in
objectivity according to the verbal definition furnished to the respondents.
Certain traits have proved to be sufficiently objective to justify fully a
genetic analysis of family pedigrees provided by lay respondents. A com-
panion study utilizes the objectivity appraisals of traits for evaluating the
significance of the correlations between siblings with respect to the same
group of traits.

Other studies based on family schedules. In connection with major studies,
it has been incidentally possible to record from the family schedules addi-
tional data contributing to a clarification of other problems. Data now
await analysis upon hair color in families selected to check upon the hy-
pothesis of transmission reached in the autosomal linkage studies, upon age
changes in hair color, and upon the contribution of the grandparent genera-
tion to the abilities of the offspring generation.

Potential marital selection in a Negro group. In collaboration with Dr.
Steggerda, who secured the results of a student poll at Tuskegee Institute
on traits desired in an "ideal" husband or wife, analysis of data has been
made together with a comparison with similar data in the literature for
white students. The results give evidence that the Negro men, regardless
of their own traits, tend to select according to culturally accepted norms,
while the Negro women show a greater tendency toward homogamy. The
Negroes of both sexes express certain preferences that tend to distinguish
them from white groups. The homogamy correlation coefficients for traits
of respondents and traits desired in ideal spouses tend to be higher than those
found in other studies for the traits of actual spouses.

Contribution of nature and nurture to average group differences. A prob-
lem that arose out of a 1937 Milbank Fund symposium stimulated a study
on intelligence hierarchies according to socio-economic group. Most of the
former studies which have attempted to separate the contributions to mental
development of heredity and environment have considered the problem
solely with reference to individual differences from a group norm. For
students of population it is perhaps even more important to have some
method of appraising the hereditary and environmental factors contributing
to differences between the mean abilities of identifiable groups (e.g., off-
spring of parents in professional vs. skilled labor occupations) . A method
was devised for using data from available studies of the mental abilities of

320

CARNEGIE INSTITUTION OF WASHINGTON

foster children and control "own" children having comparable home back-
grounds. Professor Sewall Wright kindly collaborated in a "path coefficient"
demonstration of the validity of the method. The accompanying figure
shows the relationships upon which the demonstration and the calculations
depend. Child's intelligence (IQ) can be represented as completely de-
termined by two factors: heredity (i.e., the child's genetic constitution) and
total environment, which may be (and undoubtedly are) more or less cor-
related with each other in the control group. Occupational status of father
is clearly correlated with the child's total environment. The increased dif-
ferences in the control data indicate that it is also correlated with the child's
heredity in the controls. The reasons (involving father's intelligence) need
not be represented. The conclusion was reached with respect to mean oc-
cupational group differences (of offspring) in our urban culture that nature
contributes proportionally two-thirds to three-fourths, and nurture the re-
mainder.

Occupation
Group

Child's

dotal

Environment

Ten - PC£ VE0 + Pen ?ho (Control)

Child's
Heredity

■CO
I

Im = rrF F

CE L FO

(foster \
[t'ho-OJ

Fig. 1

Child's
IQ

Participation or cooperation in related activities. Membership and par-
ticipation in related professional activities has been continued: American
Psychological Association and Eugenics Research Association (papers pre-
sented at annual meetings), American Eugenics Society, Society for Research
in Child Development, Advisory Research Board of Hudson State Industrial
School for Girls, psychological seminar at New School of Social Research,
critical reviews contributed to various professional journals.

Grateful acknowledgment is made to Dr. Streeter, Dr. Blakeslee, Dr.
Davenport, Dr. Laughlin, and Dr. bridges of the Carnegie Institution for
helpful counsel, to Mrs. Jean C. Challman and Miss Anne T. Swindell, who
served as field assistants, and to Mrs. Frances Carlson, office assistant.

Davenport, Charles B,, Cold Spring Harbor, Long Island, New York.
Investigation on child development. (For previous reports, see Year
Books Nos. 34-36.)

During the year under review the writer has continued working up the
results of some fifteen years of repeated observation on the development

GENETICS 321

of individual children. This has involved the reduction of a truly formi-
dable mass of material. At the present time the work is being continued
on the growth of some dozen absolute dimensions of the cranium and some
ten ratios between the dimensions; also, seven absolute measurements
upon the face and the growth changes of six facial proportions; the devel-
opmental changes of six eye dimensions and four ratios in which they are
involved; three absolute dimensions of the external ear (pinna) and ratios
in which they are involved.

The results of the activities of the year have been incorporated in eleven
publications, as listed.

On the occasion of a report to the American Society of Anthropologists
emphasis was laid upon the need of a better foundation for our work upon
the measurement of the living body as a basis for comparative studies of
the growth of children. The errors in measurement are pointed out and
consist of three types. First are observational errors including (1) errors
in locating landmarks; (2) errors in measuring between two landmarks;
(3) errors that arise from instrumental errors or defects; (4) the personal
error. In addition to these subjective errors are objective errors due to
variation in the object that is being measured; in repeated measurements of
the same child one of the greatest difficulties is to secure the same posture
in successive measurements. In addition there are variations connected
with time of the day and the season of the year, and, finally, there are
certain accidental errors connected with the reading and recording of the
observations. The only way to avoid these errors is by checking, which
can be accomplished by repeated measurements of the same dimension
either with the same or with different technique.

A paper was prepared on the "Postnatal growth of the external nose"
which has been presented for publication. The principal problems con-
sidered in this paper are: How are the size and form of the external nose
determined? By what road does it attain its final proportion? How does
it come to be so remarkably similar in both of identical twins? Light on
this question was gained by measurement on fetuses, infants, and children
between three and twenty years of age. The data discussed are both from
masses, giving size-age curves, and from repeated individual measurements,
constituting so-called longitudinal series. The data considered consist of
five absolute dimensions and eight ratios. Nasal height increases pari passu
with stature and attains a greater size in boys than in girls. The nasal
height in proportion to body height is the same in both sexes. The individual
curves of growth of nasal height show an adolescent spurt correlated with
that of stature. The factor (hormone) that makes that spurt affects even
the smallest of organs. The individual curves all run upward with age,
but do not run parallel. Some dimensions stop growing early while others
continue a vigorous growth. And in the different races the growth is dif-
ferent. In brothers the curves of growth are, typically, parallel but located
at different levels, while in identical twins the curves are practically identical.

The growth of nasal depth follows a segment of the sigmoid curve. The
nose in dwarfs and cretins is at first a shallow one. Some of our dwarfs,

322 CARNEGIE INSTITUTION OF WASHINGTON

independent of treatment, show a spurt of growth of nose at their (retarded)
adolescence; and a treated cretin responds by deepening of the nose.

The nasal width grows rapidly before birth, corresponding to its early
development in phylogeny. This dimension in Negroes continues from
birth its precocious prenatal size.

The growth of the nasal salient nearly ceases temporarily at about one
year, probably owing to development of the maxillae and tooth germs. This
curve has a smoother growth in girls than in boys, since in the latter the
curve is depressed by the thickening of the maxilla due to development
of the large permanent incisors and later by the thickening of the skin
of the lips as hair follicles enlarge with the growth of a mustache. Ac-
cordingly, the curve of nasal salient in the male is very complex.

The ratios of nasal proportions often develop in complex fashion. The
width-height ratio diminishes rapidly prenatally from a mean of 115 to
98, to reach a mean of 67 at maturity. Four types of growth curves between
6 and 18 can be distinguished; increasing, decreasing, U-shaped, and ir-
regular. There is a sort of "struggle" between the vertical and horizontal
dimensions during development, resulting, nevertheless, in family resem-
blance. Three indices show a reversal of slope immediately at or shortly
after birth. Indeed, in the development of nasal proportions the bones and
cartilages of the face seem quite plastic, but, nevertheless, work toward a
predestined hereditary form.

In working toward the predestined end the outer nose goes along the
mammalian path. Its beginnings are at the sides of the embryonic head.
The cartilaginous support of the nose is laid down as a pair of tubes as
in all primates; later, it breaks up into proximal and distal segments as
in anthropoid apes. The elevated root of the nose is a strictly human
trait; it is one of the last developed in the child.

A paper on "Bodily growth of babies during the first postnatal year,"
as described in the last Year Book, was published by the Institution as
one of the Contributions to Embryology. As a by-product of this paper
was published "Interpretation of certain infantile growth curves," read
before the National Academy of Sciences. In this paper attention is called
to the fact that the ratio of the upper and lower segments of the arm in
babies is a variable one during development. Thus, for some weeks before
birth the lower distal segment is growing the more rapidly. Indeed, at
birth it sometimes happens that the ratio of the two segments is 1:1 in
children as in some of the anthropoid apes ; but whereas in anthropoid apes
the ratio continues to rise, reaching 1:1.55 in the adult gibbon, in the case of
the child the growth of the distal segment is much retarded after birth,
while the proximal segment goes on growing so that the eventual ratio of
1:0.85 characteristic of the adult is achieved. The question raised is, Why
this slowing up in the growing of the distal segment? It is suggested that
there is no inherent inability of the radius to grow as fast as the humerus,
both because it does so before birth and because in other primates it con-
tinues to do so. It would seem rather that a new inhibiting gene has
become active in the human infant to slow down the growth of the radius.
This special gene, which causes the relative slowing down of water imbibition,

GENETICS 323

cell proliferation, and collagen formation at the ends of the radius, has
given man a special advantage which has aided his survival.

Certain incidental publications were prepared to meet special requests
or emergencies. As Chairman of the Committee on Biographical Memoirs,
the writer prepared the biographical memoir of George Davidson for the
National Academy of Sciences, since the preparation of this memoir has
been delayed for some forty years. As a member of the Committee on the
Social Economic Goals of America of the National Education Association,
he participated some years ago in the preparation of the first chapter of
their just-published book on Implications of social-economic goals for edu-
cation, entitled "Hereditary strength." Also, he prepared Appendix 31,
entitled "Eugenics," in How to' live.

In order to be in a better position to take a general view of the problem
of child growth, the writer accepted the invitation of the Editorial Com-
mittee of the new Annual Review of Physiology, to prepare the chapter on
growth, in which it is proposed to review the important literature on the
subject that has appeared in the last two years.

Dobzhansky, Th., California Institute of Technology, Pasadena, California.
Genetic structure of natural populations.

In the past decades studies on the mechanics of the transmission of
hereditary characters constituted the main task of genetics. Great strides
forward have been accomplished in this field: the structure of the hereditary
materials has been, by and large, clarified; the relationships between the
hereditary particles, genes, and their physical carriers, chromosomes, under-
stood; accurate quantitative methods for studying inheritance worked out.
It is the availability of these exact methods that permits an approach to an
even broader and more recondite problem, namely, that of the hereditary
constitution of complexes of individuals, populations, races, and species.
This problem is certainly not a new one, going back, as it does, at least to
Darwin; yet only comparatively recently has it come truly within reach
of modern genetics. The small flies belonging to the genus Drosophila fur-
nish as favorable material for investigations in this field as they do for those
along the now classical lines of the genetics of the transmission of hereditary
characters. The following is a progress report covering the work on a genetic
analysis of certain populations of two species, Drosophila pseudoobscura
and D. azteca.

Samples of natural populations of Drosophila were taken in ten localities
in Mexico and in eleven localities in Guatemala. A total of 194 living strains
of D. pseudoobscura and 39 strains of D. azteca were brought to the labora-
tory, where most of them are being perpetuated. Besides these, several living
strains of other species of Drosophila, some of them new to science, were
secured. Added to the group of strains of D. pseudoobscura and D. azteca
already present in the laboratory, these new strains form a part of a geo-
graphical collection of living lines in which practically every part of the dis-
tribution area of the above two species is represented.

Population samples of D. azteca are being worked out in collaboration
with Professor D. Sokolov, of the Escuela Nacional de Ciencias Biologicas,

324 CARNEGIE INSTITUTION OF WASHINGTON

Mexico. D. azteca has five pairs of chromosomes, including a V-shaped
X-chromosome, three pairs of autosomes with a subterminal or a submedian
spindle fiber attachment, and one pair of dot-like microchromosomes. In
the nuclei of the larval salivary glands these chromosomes are represented
by six long and one very short strand; two of the long ones correspond to
the X-chromosome and the short one to the microchromosomes. Reference
"maps" showing the disk patterns in all the salivary gland chromosomes of
an arbitrarily chosen standard strain were prepared. Any deviation from
this normal or standard gene arrangement observed in other strains may
now be described in terms of the standard maps.

All the strains of D. azteca were outcrossed to the standard strain, and
the chromosomes were studied in the salivary glands of the hybrid larvae.
If the hybrids have seven normally paired chromosomal strands, it follows
that the strain tested has the same gene arrangement in all the chromosomes
as the standard one. Any difference in the gene arrangement results in forma-
tion of characteristically abnormal pairing configurations, from the inspec-
tion of which the precise nature of the difference may be deduced. Indeed,
strains of D. azteca prove to be frequently different from each other in the
gene arrangement. All the variations thus far detected are due to inversions
of blocks of genes within a chromosome.

A total of three gene arrangements has been established in the long, and
two in the short limb of the X-chromosome, six in A-chromosome, and four
in B-chromosome. Several gene arrangements may be found in the popula-
tion inhabiting the same locality, and even in the offspring of a single female
or male caught in nature. Nevertheless, in no locality is the entire variety
of the gene arrangements present ; on the contrary, the species is geographi-
cally differentiated, so that strains coming from geographically remote re-
gions are more likely to have the chromosomes differently constructed than
strains from the same locality. Thus, all the strains from Guatemala and
south central Mexico have a gene arrangement in the X-chromosome that
apparently does not occur in California strains; in north central Mexico
(Durango) both the southern and the California arrangements occur in the
same population. It is justifiable to speak of the formation of chromosomal
races in D. azteca.

Some of the gene arrangements found in A- and B -chromosomes proved
to be related to each other as overlapping inversions. As shown by Sturte-
vant and Dobzhansky, overlapping inversions permit the construction of
phylogenetic schemes indicating the manner in which the gene arrangements
in question may have descended from each other. Such phylogenetic schemes
have been prepared for A- and B-chromosomes of D. azteca. Among the
gene arrangements known in A-chromosome those forming one end of the
phylogenetic chain occur only in Guatemala and southern Mexico, and those
forming the other end only in California. The arrangements occupying the
middle portion of the chain occur in north central Mexico (Durango). On
the basis of facts such as these certain inferences regarding the history of
the species and of its distribution and migration in space become possible.

The "sex ratio" condition previously known in D. obscura, D. pseudo-
obscura, and certain other species has been found also in wild populations

GENETICS 325

of D. azteca. Males carrying the sex ratio factor in their X-chromosome
produce mainly daughters, and few or no sons. The sex ratio condition in
D. azteca is associated with a triple inversion in the long arm of the X-chro-
mosome. The three inversions are independent, that is, separated from each
other by segments of the chromosome that have the same gene arrangement
in chromosomes carrying and not carrying sex ratio. It is not easy to see
what mechanism keeps these three inversions in the same chromosome and
does not permit them to be separated by crossing-over with normal chromo-
somes.

An analysis of the population samples of D. pseudoobscura from Mexico
and Guatemala is now in progress, so that only very preliminary results can
be reported. This analysis is being carried on along two main lines: a cyto-
logical study of the variations in the gene arrangement, and detection of
the concealed genie variability in the third chromosome. The gene arrange-
ment is highly variable in Mexican and Guatemalan populations. Altogether
nine arrangements, one of them not known previously, have been found.
The relative frequencies of the different arrangements are unequal in popu-
lations from different localities. In this respect populations from central and
southeastern Mexico form one group; those from west central Mexico form
another; those from Guatemala the third. Even within these regions no
uniformity prevails ; populations inhabiting a given locality may vary rather
independently from those living in neighboring localities. For example, 14
out of the 90 third chromosomes analyzed from Pachuca (Hidalgo, Mexico)
proved to have the "Olympic" gene arrangement. The Olympic arrange-
ment is known also from the Olympic Peninsula, Washington, and from the
vicinity of Patzcuaro (Michoacan, Mexico), but it has not been found in
localities relatively much closer to Pachuca. This suggests that the fre-
quency of a given chromosome structure, or a given gene, in a population
may be subject to large fluctuations due to isolation and to restriction of
the effective size of the breeding population. Such fluctuations were postu-
lated on theoretical grounds several years ago by Sewall Wright.

It has been shown before that in natural populations of D. pseudoobscura
inhabiting certain mountain ranges in California about 12 per cent of the
third chromosomes carry recessive lethals, 3 per cent semi-lethals, and about
40 per cent genes causing minor decreases in the viability. Preliminary data
for Mexican and Guatemalan populations seem to indicate an even greater
infestation of the germ-plasm by deleterious recessives. Among the 120 wild
third chromosomes analyzed, 25 chromosomes, or 20.8 per cent, carry lethals,
and at least 9 chromosomes, or 7.5 per cent, definite semi-lethals. The fre-
quency of the modifiers of the viability that are not classed as semi-lethals
is not yet determined, but it is certain to be very high.

METEOROLOGY

Bjerknes, V., Oslo, Norway. Preparation of a work on the application of
the methods of hydrodynamics and thermodynamics to practical meteor-
ology and hydrography. (For previous reports see Year Books Nos.
5-36.)

Investigations. Professor J. Bjerknes and Dr. E. Palmen finished in the
fall of 1937 their aerological investigation of Case 4, February 15-17, 1935
(mentioned in previous reports; published in Geofysiske Publikasjoner,
Oslo, 1937). That investigation, together with three earlier ones in the
same series, will now form the empirical basis for the textbook treatment
of the dynamics of cyclones, with which J. Bjerknes is at present occupied.

The fundamental problem of the cause and origin of pressure varia-
tions, which must be tackled in any thorough treatment of the dynamics
of the atmosphere, has found a satisfactory solution through a simple
mathematical theory developed in connection with the aerological investi-
gations. J. Bjerknes presented that theory at the annual meeting of the
Deutsche Meteorologische Gesellschaft in Frankfurt in October 1937 and
published it in the Meteorologische Zeitschrift in December 1937. The
theory is "quasi-static" and states that the pressure variation at a fixed
point of an arbitrary level h is due to the combined action of the following
three processes: (1) Vertical air motion effect. Upward motion at the
level h increases (and downward motion decreases) the weight of the air
column above h, and the pressure at the fixed point varies accordingly.
(2) Horizontal advection effect. In the general case, when horizontal den-
sity gradients exist, horizontal advection either increases or decreases the
weight of the air column above h and thereby influences the pressure at
h in the same sense. (3) Horizontal divergence and convergence effect. If
horizontal divergence prevails from h upward, the weight of the fixed air
column above h decreases, and the pressure at its base decreases in con-
sequence. If convergence prevails, the opposite result takes place.

The vertical air motion effect vanishes at the earth's surface, wherever
this is strictly horizontal. In the free atmosphere, however, the vertical
air motion is often the cause of important pressure variations. In fact,
the upper "lows" initially form by the descending motion over polar air
which spreads along the ground behind the polar front waves. Likewise,
at the initial formation of an upper "high" the ascent of tropical air plays
an important part.

The horizontal advection effect is represented in typical form at the
frontal surfaces and produces, when acting alone, a fall of pressure in front
of warm fronts and a rise of pressure behind cold fronts. The tropospheric
and stratospheric contributions to the advection effect are systematically
of opposite sign, usually with the tropospheric part predominating.

The horizontal divergence and convergence effect explains, among other
things, the propagation and partly also the intensification of the upper
perturbations. Provided that the air of the general upper current goes
faster than the perturbation (a condition which is usually fulfilled), diver-

326

METEOROLOGY 327

gence and fall of pressure is developed ahead of the upper "low" and con-
vergence and rise of pressure is developed behind it.

Both the advection and the divergence (convergence) effects bring in the
influence of all upper layers, even the very light uppermost ones, on the
variations of barometric pressure at the level h. It is, however, evident
from the mathematical expressions of these effects that the influence of a
layer of unit thickness becomes smaller the higher up it is situated. The
theories based on a preponderating influence of stratospheric processes, which
have played a great part in meteorological discussions of recent years,
therefore must be refuted.

Redactional work. The manuscript of the new edition of part I, "Statics,"
may be considered as practically completed (170 typewritten pages and a
considerable number of illustrations). This will in print be a book of
about the same size as the old edition, but with a much richer content.
Large parts of the old book could be abbreviated, since the innovations
it introduced have been universally accepted (units, proper variables, etc.).
Special sections have been devoted to radiation and to atmospheric thermo-
dynamics, which were not treated in the old edition. The theoretical parts
of the volume have been written by Dr. Godske, the section on aerological
methods by Godske and J. Bjerknes.

The manuscript of the new edition of part II, "Kinematics," may also be
considered as almost completed (150 typewritten pages plus numerous
illustrations). This volume will consequently but slightly exceed the size
of the old edition, but the content is more exhaustive than before for
reasons similar to those given above. An addition of considerable practical
importance deals with Dr. Petterssen's "kinematical prognosis," and with
the problems of frontogenesis and of frontolysis. The entire volume has
been written by Dr. Godske.

The greatest progress of the year consists in the preliminary redaction
of the theoretical chapters of part III, "Dynamics." Numerous attempts
at giving form to these chapters have been made during the last twenty to
thirty years. The difficulties met therein are chiefly responsible for the
delay in the finishing of our work. At first there were no definite goals
to aim at, and we tried to develop the theoretical tools for dealing with
problems of a rather indeterminate character. But, as time went on, the
empirical discoveries made the main problems take more precise forms.
Then the question arose to what extent these problems could be mastered
mathematically. We have now reached a point where we know fairly well
to what extent this is possible with our present empirical knowledge and
with our present mathematical resources.

It has now proved possible to write a first, relatively complete, draft
of the theoretical part of the volume. The work has been mainly in Dr.
Godske's hands. He has written a manuscript of about 250 pages divided
into the following five chapters: (1) the hydrodynamical equations of mete-
orology (34 pages) ; (2) discussion of the hydrodynamical equations by use
of line integrals (31 pages) ; (3) special motions, steady and others (51
pages); (4) stability and instability; turbulence (61 pages); (5) equations
of perturbations and the wave theory of cyclone formation (69 pages).

328 CARNEGIE INSTITUTION OF WASHINGTON

Although the manuscript is a preliminary one, there is no reason to expect
that much rewriting will be necessary.

The remaining part of the volume will be of empirical and practical nature
in closest possible contact with the theoretical part. It will finally present
the methods of weather map analysis and of weather forecasting. The work
will be mainly in the hands of Dr. Godske and Professor J. Bjerknes, with
the advice of other investigators, as Dr. Bergeron and Professor C. G.
Rossby (of the Massachusetts Institute of Technology, Cambridge). It
may be hoped that the preliminary manuscript of the remaining chapters
of part III will be ready in the course of the coming year. After that only
the last finish remains to be given to the entire volume as well as to the
entire work.

NUTRITION

Ritzman, E. G., University of New Hampshire, Durham, New Hampshire.
Cooperative researches on the nutritional physiology of the adult
ruminant.

With the retirement of Dr. F. G. Benedict during this year the results of
our cooperative researches carried on at Durham on cattle have been com-
piled and made public (The nutritional physiology of the adult ruminant).

The studies in animal nutrition carried on cooperatively with the Nutrition
Laboratory of the Carnegie Institution of Washington have been primarily
of a fundamental nature. The attempt has been to build a more solid foun-
dation of physiological fact for the still relatively uncertain structure which
is now available as guide in the practical requirements of feeding livestock
economically.

During the past nineteen years of our cooperation this laboratory has
carried out many metabolism experiments with many animals of different
species of farm live stock. These represent 13 experiments with horses,
including a thoroughbred stallion with a notable turf record, a blue-ribbon
Percheron stallion weighing over a ton, a Percheron mare, a standardbred
or trotting gelding, a range pony, and a very small Shetland pony weighing
about 300 pounds ; about 300 experiments with eighteen beef steers ; 4 experi-
ments with bulls; over 50 experiments with twelve dairy cows; over 200
experiments with about one hundred sheep ; about 30 experiments with thir-
teen goats ; and 20 experiments with pigs ranging from a boar weighing 600
pounds down to suckling pigs weighing less than 10 pounds.

The primary objective has of course always been to determine basic
physiological principles to serve as a solid foundation on which problems
of immediate practical concern can eventually be solved more intelligently.
These problems relate not only to the best economic interests in feeding of
livestock, but also to nutrition as it affects health and efficiency, so that a
sound physiological background of the animal organism as a transformer
of energy has a potential significance in its application beyond the particular
species on which it has been determined.

These researches have brought out many new facts of interest relating
both to technique of conducting such work and also to metabolism and
nutrition, many of which have previously been made public in the form of
bulletins, contributions to scientific journals, and monographs.

These studies have in a large measure been devoted to a determination
of the needs of the animal organism for its own maintenance (i.e., basal
metabolism) in support of life under various conditions of season and cli-
mate, and particularly to the comparative efficiency of the different species
of farm livestock as energy-consuming organisms. Thus it has been found
that the horse has the highest basal metabolism per unit of size of any animal
so far measured. It is nearly twice that of the rat, the goat, and even of
man, a fact which may explain this species' extraordinary capacity for speed
and endurance, but likewise indicates a higher need for maintenance.

The outstanding feature of these investigations is the discovery that the
influence of certain factors affecting the basal metabolism of adult dairy

329

330 CARNEGIE INSTITUTION OF WASHINGTON

cattle has heretofore been entirely unsuspected. These factors relate pri-
marily to (1) the remarkable lability of the basal metabolism of adult cows
and the tendency of the basal metabolism to vary in this genetically highly
specialized animal, and (2) the extraordinary effect of lactation on increase
in basal metabolism. The concept held for many years that the rate of
metabolism, or basal heat production, is conditioned solely by the rate of
heat loss to the environment is thus rendered untenable. The results from
comparative types (such as highly developed beef and dairy stock) suggest
the far more logical theory that basal heat production varies with functional
adaptations and their respective requirements and that these are determined
by internal factors (hormone stimulus).

While these studies have heretofore been carried out entirely on adult
individuals, a study of the metabolism during growth, on which relatively
but few experimental data exist, has been begun during this year. This has
been carried out with eight Holstein heifer calves from purebred ancestry
whose annual milk production records are known.

It is planned to study these heifers periodically from the age of about
eight months (when the experiments were begun) through at least one and
possibly two lactations. Thus three series consisting of sixteen complete
energy and nitrogen balances and twenty basal metabolism measurements
were carried on during this past year (July 1, 1937 to July 1, 1938).

Besides the more immediately practical ends of determining the energy
and protein requirements during growth, this study presents critical physio-
logical potentialities. Thus this first year's results have already demon-
strated an extraordinarily high tissue stimulus during growth, which is nearly
double that of the adult dry and farrow cow and compares more nearly with
that of the adult when lactating. The interrelationship between the tendency
to early maturity, a high lactating potential, and a differential in degree
of tissue stimulus (i.e., basal metabolism) presents many attractive problems
for the physiologist, which may help to build a foundation or basis for pre-
dicting the eventual producing ability in young dairy stock, which has so
urgently been sought by dairymen.

In a series of experiments carried out monthly throughout the year on an
adult Chester White pig a considerable variation in basal heat production
was obtained although the food and the experimental temperature were
maintained constant throughout the series. The highest basal metabolism
(19.2, 19.3, 19.0 calories per kilogram body weight) occurred during March,
April, and May, and the lowest (15.5, 14.9, and 14.3 calories per kilogram
body weight) was obtained respectively during the months of June, July,
and August. While the extreme difference (about 35 per cent) reflects a
tendency to vary somewhat similar to that already reported for adult dairy
cows, the high values appear earlier in spring and the lowest basal heat
production of the pig occurs during the months of highest basal heat pro-
duction by the cows. At present this can be explained only by difference
in life habits of the two species, particularly during the hot season from June
to August, when the cows were kept on pasture exposed to sunlight and
other variable weather conditions during the entire day (except of course

NUTRITION 331

during the actual period of the experiment), while the pig was kept in a
shaded pen.

These results obtained on the pig tend, however, to support the general
conclusions suggested by the results with adult dairy cows relative to a
lability in the basal metabolism and its causes.

A series of experiments at different environmental temperatures ranging
from 11.0 to 24.1° C. showed no effect of temperature changes on the basal
metabolism within these limits, suggesting that the improved breeds of this
species have a sufficient insulation of fat to protect them against a drop in
temperature at least down to the neighborhood of the freezing point.

Subsequent to this series of seasonal range of experiment, the pig was
bred and its basal metabolism was measured monthly until one week after
parturition, that is, into the early stage of lactation. At 41 days of pregnancy
the basal metabolism was only 6 per cent above the previous level, at 75
days it was 43 per cent above, and at 103 days (11 days before farrowing)
it was 53 per cent above original basal level. If we correct this latter value
(which would be the only one materially affected) for the seasonal influence,
it becomes 45 instead of 53 per cent. The influence of pregnancy is then
along the order previously reported for sheep (New Hampshire Exper. Sta.
Tech. Bull. 45, and reprint from Wissensch. Arch. f. Landwirtsch., Abt. B,
Arch. f. Tiererndhrung u. Tierzucht, vol. 5, no. 1, pp. 64-67, 1931). The
significant feature is the extraordinary influence of lactation on the basal
metabolism, which at this early stage is 62 per cent above the original basal
level. This again, as reported for cows (Carnegie Inst. Wash. Pub. No.
494), indicates the tremendous internal stimulus to which the tissue cells
of the body are subjected in the process of milk formation.

The difficulties met in locating some firm capable and willing to build a
suitable mask has delayed the proposed project of studying the effect of
work on the energy expenditure of the horse. This has now been overcome
and the necessary preparations will be completed so that preliminary ex-
periments may be carried out within a few months.

A series of experiments have also been begun to study the effect of inges-
tion of pure sugars (glucose) on the respiratory quotient of the ruminant.
Three experiments with glucose and two controls have so far been carried
out on goats. These are merely a contribution to the larger program carried
on by Dr. T. M. Carpenter in a study of the effect of sugar on metabolism
which has been under way for several years.

Sherman, H. C, Columbia University, New York, New York. Influence
of nutrition upon the chemical composition of the normal body. (For
previous reports see Year Books Nos. 32-36.)

Last year we reported the completion of the experiments upon the relation
of food to length of life, made possible by grants from the Carnegie Cor-
poration of New York through the Carnegie Institution of Washington.
The data of the last of these experiments have now been prepared for tech-
nical publication in the Journal of Nutrition. The two outstanding results
of the five years' research thus completed are (1) the finding that scientific
adjustment of the quantitative proportions of a simple mixture of natural

332 CARNEGIE INSTITUTION OF WASHINGTON

foods yielded as favorable an outcome in nutritional well-being and length
of life as did more diversified diets, and (2) that calcium, vitamin A, and
what we previously called vitamin G and now call riboflavin were all sig-
nificant factors in our previously recorded nutritional improvement of an
already adequate dietary.

One of the by-products of that research was the finding that well-diversi-
fied dietaries no poorer in calcium than are sometimes met in ordinary
human experience may, when long continued, result in a decline of well-
being apparently due to a lowered calcium content of the body. More
directly in line with the constructive aim of our research as a whole is the
converse question thus suggested: whether increasing the level of the nutri-
tional intake of calcium from one of slightly above minimal adequacy to the
more liberal intake which induces more nearly optimal results in our full-
life and successive-generation feeding experiments would be found measur-
ably to increase the calcium content of the normal body. With the approval
of the President of the Institution the small balance remaining from the
grant in aid of the previous work has been devoted to this new research.

Two main series of experiments were begun, using as respective starting
points or basal dietaries the Diets A and B which have been described in our
reports upon the preceding research. (Tentatively, and to a limited extent,
these are being supplemented by experiments employing diets of higher
protein content.)

The general principle of constancy of chemical composition among the
normal members of a species, a hypothesis which has been so widely influen-
tial, and for so long a time, as to have been called "Liebig's law of the
minimum," had tended to bias biochemical thinking against the idea that
nutrition could significantly influence an already normal percentage of any
chemical constituent of the essential tissues of the body. But the present-
day dynamic view of physico-chemical phenomena which suggests that the
introduction of different amounts and proportions of such active factors as
certain salts and vitamins into the system must be expected to shift some of
its concentration levels and equilibrium points, and the definite objective
findings of nutritional improvement of the already normal in our full-life
and successive-generation feeding experiments, now together reopen the
fundamental questions, how specific is a species in its quantitative chemical
composition? and to what extent or how significantly may the nutritional
intake influence the body composition within a normal range?

Here, as in our investigation of the influence of food upon general fitness
and upon length of life, the experiments yield clearer evidence when con-
tinued into a second generation. In our first series of such experiments,
parallel families or breeding lots were made up at the end of infancy (rats
at four weeks or one month of age) and thenceforward received, respectively:
(1) the original or basal Diet 16, also designated as Diet A in some of our
publications, which is known to be adequate in that families are thriving
on it in the forty-fourth generation, but which in its calcium content of
0.20 per cent of the dry matter is probably but slightly above the level of
minimal adequacy for permanently satisfactory results generation after
generation; (2) Diet 168, made by adding to Diet 16 enough calcium car-
bonate to raise the calcium content to 0.64 per cent; (3) Diet 169, made by

NUTRITION 333

the further addition of calcium salts, in this case carbonate and phosphate,
to bring the calcium content to 0.80 per cent with the same ratio of calcium
to phosphorus as in Diet 168.

Offspring of the families on these three diets have been analyzed for cal-
cium at the ages of one, two, three, six, and twelve months of age, i.e., at
fixed points ranging from the end of infancy to full adult status in the rat.
These results show: First, the normal process of calcification in the growing
body was greatly expedited by the more liberal levels of calcium content of
the family food supply. Throughout a long period of rapid growth the
young from the families having liberal-calcium food contained from one-
fourth to one-half more body calcium (reckoned either in amount or in per-
centage) than did their cousins from families which were receiving a dietary
of only slightly above a minimal adequate calcium content. Secondly, it was
found that the percentage of body calcium as "plateaued" in the adult was
permanently higher for those on the dietaries of liberal calcium content. In
other words those which received a dietary of slightly over minimal ade-
quate calcium level never fully caught up, in the percentage of calcium in
their bodies, with those whose dietaries were three- or fourfold richer in
calcium.

These findings show a larger influence of nutrition upon at least one aspect
of the composition of the normal body than could have been anticipated
from the long-accepted generalization which we now see to have been too
dogmatic. As a basis for the more discriminating generalization now needed,
it is clearly desirable to develop this research in at least two directions: the
further study of calcium from different dietary starting points, as men-
tioned above; and experiments with graded levels of intake of other essen-
tials, to measure their effects upon the body-concentration levels of these
substances themselves and of others with which they may be interrelated
in the nutritional process.

The significance of this may perhaps be more fully apparent when viewed
as a substantial revision not only of Liebig's generalization but also of its
physiological corollary formulated by Claude Bernard in his well-known
saying that it is the fixite of the internal environment which enables an
organism to cope with a new or changeable external environment. Useful
as this idea has been, it now stands in need of revision. The postulated
"fixite" of the internal environment is only an approximation. Its flexibility
and the influence thus exercised by nutritional differences within the normal
range can now be seen as measurably influencing the quality and duration
of life. We hope now to explore the possibilities of obtaining further light
in this field through the direct approach of quantitative chemical investiga-
tion of the tissues of animals, all normal, but differently fed. This chemical
information is to be sought in part by the methods of chemical analysis as
hitherto understood and in part by recently developed quantitative feeding
methods.

The validity of these new methods of research and the far-reaching sig-
nificance of such differences as can be nutritionally induced within the
normal body are encouragingly indicated by the preliminary results already
obtained.

334 CARNEGIE INSTITUTION OF WASHINGTON

The efficient services and constructive suggestions of those who have col-
laborated in this investigation, whether as research assistants or as volun-
teers, are gratefully acknowledged.

Vickery, H. B., New Haven, Connecticut. Continuation and extension of
work on vegetable proteins. (For previous reports see Year Books

Nos. 3-36.) *

The comparative studies of the new salt mixture 351, reported in 1937
(Year Book No. 36), with the old Osborne and Mendel salts have been
continued. Experiments on reproduction and on longtime growth have indi-
cated that the new mixture is well adapted for rapidly growing albino rats.

In the earlier work, it was shown that, if the food contained either 2 g.
of salt mixture 351 or 4 g. of Osborne and Mendel salts, growth of the
male albino rat at a rate in excess of 5.0 g. a day for the period of growth
from 60 to 200 g. body weight could be expected. With foods that contained
either salt mixture in the amounts indicated, the animals would, if permitted
free access to food, consume on the average about 50 mg. of calcium and
34 mg. of phosphorus per day, and the ash of the dry fat-free femurs would
be approximately 58 to 60 per cent. The more recent studies have been
directed toward a determination of the exact requirement for calcium and
for phosphorus for different periods of growth. To aid in this study, a
salt mixture, no. 371, similar in composition to 351 salts except that it
does not contain calcium and phosphorus, has been used. It is thus possible
to vary the amounts of calcium and phosphorus to be added to the food
without making changes in the proportions of the other inorganic constit-
uents and also to compare results obtained with those observed when the
standard salt mixture, 351, is used as the source of inorganic constituents
of the food. In the work of this laboratory, this new salt mixture has
replaced the calcium- and phosphorus-free one (XXX) used by Osborne
and Mendel in 1926, and in subsequent years in the investigations that
were conducted in collaboration with Dr. E. A. Park. The composition
of salt mixture 371 is as follows:

MgC03 58.0 grams

MgS04 38.0

NaCl 162.0

KC1 260.0

K2C03 197.0

Citric acid 209.0

Ferric citrate 70.0

KI 0.75

MnS04 0.85

NaF 2.3

A12(S04)3K>S04 0.4

CuS04 2.2

The quantities refer to "reagent" or "c.p." salts.

A satisfactory technique for feeding measured amounts of calcium and
phosphorus each day has been developed. The general method of experi-
mentation has been described before (Year Book No. 31). Male albino

NUTRITION 335

rats are fed the measured amounts of calcium and phosphorus salts from
weaning (21 days of age and 50 to 55 g. body weight) until growth is
terminated at 200 g. body weight. As in work previously reported, the ash
of the dry fat-free femurs is used as a measure of the degree of calcification.
The early results indicate that it may be definitely advantageous to the
development of the skeleton of the rat to vary the proportions of calcium
and of phosphorus with changes in body weight. A final report on these
experiments will be given in a journal paper later in the year.

The effect of the intraperitoneal injection of thymus extract on the growth
and development of the albino rats of this colony has been studied at inter-
vals, as material became available, since 1934. This work has been done
in collaboration with Dr. Leonard G. Rowntree of the Philadelphia Institute
for Medical Research. Dr. Rowntree has generously supplied the thymus
extract that has been used throughout the investigation. When this work
was undertaken at the suggestion of the late Professor Mendel it was hoped
that it would be possible to duplicate with the animals of this colony the
results obtained by Dr. Rowntree and his colleagues. They had demon-
strated that the offspring of thymus-injected rats showed marked accelera-
tion in early growth and in the development of certain organs. It was
planned to study the effect of this rapid development on the skeletal system.

The injection of the thymus extract has been continued through many
generations of animals in several series of experiments. In some of the
early trials there seemed to be a slight increase in the growth rate of the
offspring of thymus-injected animals in comparison with the rate of growth
of untreated animals. In recent months, however, that has not been true,
and in many cases growth has been markedly subnormal. There has never
been any indication of precocity such as early eruption of the teeth, appear-
ance of hair, and opening of the eyes, as has been reported from the Phila-
delphia laboratory. Inasmuch as the rate of growth of the animals of this
colony is so much higher than in that at the Philadelphia Institute for
Medical Research, it seemed desirable to try the effect of another stock
food, to see if, with a slower "normal" growth, there might be increased
rate of development with the use of the thymus extract. Consequently,
animals have been fed the stock ration supplied by Dr. Rowntree, and have
been given the usual intraperitoneal injections of thymus extract. The
young of these thymus-injected parents are smaller at all ages than those
from injected parents fed the regular stock ration of this colony. There
has been no evidence of precocity.

In an attempt to determine a cause for the failure of the animals of this
colony to develop more rapidly when thymus extract was administered, a
comparison has been made of the weights of the thymus glands from the
offspring of thymus-injected parents with those from animals of the regular
stock. Several years ago, Moment, working with animals from this colony,
made extensive comparisons of the organs of rapidly and of slowly grown
rats. One of the most striking observations that he made was that the
thymus gland of the rapidly grown rats was much larger than that of the
slowly grown animals. As he states in his summary: "The behavior of
the thymus is unlike that of any other organ. Its size in quick growth

336 CARNEGIE INSTITUTION OF WASHINGTON

rats is, in every group, much greater than in slow growth ones, and may
be 300 per cent greater. But the time at which the size is greatest and
that at which it gets smaller is the same in the two series, even though the
body sizes are very different." With the limited number of animals that
have been available since this phase of the work was started (only 40 from
thymus-treated parents), there has been observed a marked difference in
the weights of the thymus glands at different ages. The thymus glands
from untreated stock animals are significantly larger than those from rats
born of thymus-injected parents. The differences are not as great as those
observed by Moment in his comparison of quick-growth and slow-growth
rats.

With the aid of Dr. G. W. Pucher and of other members of the Experiment
Station staff attached to this laboratory, we have completed a study of the
behavior of the stalks of the tobacco plant when these were subjected to
culture in water, both in light and in darkness, under conditions similar to
those we employed in earlier investigations of tobacco leaves. The results
have been published during the past year in a bulletin from this station.
The stalks, denuded of all leaf tissue, were cultured for 332 hours, analyses
being made at convenient intervals so that the results could be plotted on
curves which showed the increase or decrease of the analytically determi-
nable components. Towards the end of the experimental period, shoots
appeared at the upper nodes of many of the stalks, those in darkness
developing into elongated colorless stalk-like branches with rudimentary
leaves, those in light developing into small sessile green leaves. This be-
havior was taken as evidence that vegetative processes could continue in
the material and that the experiment revealed changes in tissue that was
still alive, abnormal as the conditions of culture may have been.

The water content of the stalks at first increased slightly and then slowly
diminished; even at the end of 330 hours only 10 per cent of the initial
water had disappeared. The organic solids diminished appreciably in dark-
ness but changed very little in light. The loss in darkness was doubtless
due to respiration; the maintenance in light indicates that photosynthesis
occurred in the green cortex tissue in sufficient amount approximately to
compensate for respiration losses.

The amide nitrogen and the soluble amino nitrogen both increased and
there was a slow but significant increase in ammonia nitrogen. Evidence
of the synthesis of glutamine in light was secured, and it is probable that
the general metabolism of both glutamine and asparagine did not differ
qualitatively from that characteristic of leaves under similar conditions.
Quantitatively, however, the changes were small.

The organic acids increased slightly early in the culture period and there-
after diminished. Oxalic acid did not change; citric acid increased signif-
icantly in the dark, exactly as it does in leaves, but diminished slightly in
light. Malic acid increased both in light and in darkness though more
slowly in the latter case. The increase in darkness is in sharp contrast to
the behavior of malic acid in leaves under similar conditions.

By far the most important changes, from the quantitative point of view,
were those of the carbohydrates. Whereas in leaves the carbohydrates
increase rapidly and very materially in light but decrease rapidly in dark-

NUTRITION 337

ness, in the stalk the soluble carbohydrates diminished under both condi-
tions, although less rapidly in light. The initial soluble carbohydrate
content was much higher than is usually found in leaves of the same variety
of tobacco plant; the final value was comparable to that observed in normal
leaves. The changes can be interpreted to represent the effects of respira-
tion, the slower rate of carbohydrate loss in light being due to the compen-
satory effect of photosynthesis.

The loss of organic solids due to respiration during culture of tobacco
stalks in darkness could be accounted for fairly accurately in terms of the
loss of soluble carbohydrates. With leaves, on the other hand, the respira-
tion loss was considerably greater than the loss of carbohydrates and it
was apparent that substances other than carbohydrate were drawn upon.

Our results with tobacco leaves and stalks have been of the greatest
assistance in the interpretation of data secured during the culture of rhubarb
leaves. Preliminary experiments with this material were reported last year.
The object of our study was to see if rhubarb leaves differ in any funda-
mental manner from tobacco leaves with respect to the metabolism of nitro-
gen, of organic acids, and of carbohydrates. Differences were to be antic-
ipated inasmuch as the rhubarb plant is one of the group classified by
Ruhland and Wetzel as acid plants. These species are supposed to differ
from the more nearly neutral species with respect to the metabolism of
ammonia. In a paper published recently, we have shown that rhubarb
leaves when cultured in water in darkness become strikingly enriched in
glutamine, but the apparent increase in asparagine is small. A careful study
of the material separated by direct crystallization from the fraction that
should contain both amides failed to reveal any asparagine whatever al-
though glutamine was readily isolated in substantial yield. Treatment of
the mother liquors by methods designed to concentrate any asparagine they
might contain likewise failed to reveal this amide and gave evidence that
the substance responsible for the apparent asparagine amide nitrogen has
properties different from those of asparagine. It was concluded therefore
that glutamine is the only substance concerned in the amide metabolism of
the rhubarb plant. The marked enrichment in glutamine that occurred
during culture in darkness shows that this plant possesses an amide metab-
olism that comes into play under the special conditions of water culture
we have employed and that differs only in detail from that of the tobacco
leaf. Incidental observations on the precipitation of arginine and tyrosine
by mercuric nitrate along with glutamine were made, confirming observa-
tions recorded by Schulze many years ago. The demonstration that the
nitrogen, which, from its behavior towards hydrolytic agents, might be at-
tributed to asparagine, may in fact belong to some other substance is of con-
siderable value in the interpretation of analytical results obtained by indirect
methods. Isolation methods must clearly be used as a control on the indirect
methods in cases where one or other of the amides is apparently present only
in small proportion.

A full discussion of our results on the culture of rhubarb leaves in water
and in 5 per cent glucose in darkness, and in water in light, is now in prepara-
tion. There is little doubt that this plant possesses a mechanism for the
synthesis of glutamine that is exceptionally effective under certain conditions.

338 CARNEGIE INSTITUTION OF WASHINGTON

We secured specimens of blade tissue which, after culture for 165 hours in
darkness, contained nearly 7 per cent of the organic solids as glutamine.
Other samples were less efficient, and it appears that there may be consid-
erable variation in this respect. The leaves possess an extraordinary capacity
to transform the nitrogen of protein into ammonia during culture and are
evidently far more tolerant of high concentrations of ammonia than those
of the tobacco plant. Amide synthesis as a mechanism for the detoxication
of ammonia in the sense of Prianischnikow's hypothesis has little meaning
in a tissue that may normally contain as much as 16 per cent of its total
nitrogen and 50 per cent or more of its soluble nitrogen as ammonia, and,
while his views are very helpful in describing the behavior of the nitrogen
of tobacco leaf, they shed little light on the behavior of rhubarb. Never-
theless, the main outlines of the nitrogen metabolism during culture of
excised leaves are the same in both plants; protein is rapidly digested to
amino acids either in light or in darkness, the amino acids are deaminized
with the production of ammonia, and much of this ammonia is recombined
into the form of an amide, in the rhubarb leaf exclusively glutamine under
all conditions of culture.

It was hoped that an experiment in which rhubarb leaves were cultured
in glucose solution would shed some light on the nature of the non-nitrog-
enous amide precursor. Our work with tobacco showed clearly that the
presence of the products of photosynthesis is essential to the formation of
this substance, and it seemed possible, therefore, that the precursor is, or
is derived from, a sugar. Experiment showed, however, that glucose did
not stimulate amide formation significantly under the conditions we em-
ployed although the leaves contained much ammonia and did in fact syn-
thesize moderate amounts of glutamine. That glucose actually entered the
tissues is certain, since these leaves maintained a supply of carbohydrates
far higher than the controls, and sucrose synthesis was definitely increased.
Furthermore there was a significant increase in the malic acid.

One of the most interesting results of these experiments was a further
demonstration that leaf tissues that already contain nitrate nitrogen may
become further enriched in nitrate during culture in darkness. This obser-
vation was first made in this laboratory some years ago during experiments
with tobacco leaves and has been subsequently confirmed by us with the
same material. Rhubarb leaves show exactly the same phenomenon ; during
the first 93 hours of culture, the nitrate, particularly in the blade, may in-
crease by nearly 50 per cent of the quantity present at the start. In the
later stages of culture, it diminishes again to approximately the initial
quantity. The same phenomenon has also recently been found in Swiss
chard and in tomato leaves by Professor McKee of Connecticut College.
No adequate explanation has yet been obtained, but it seems clear that the
nitrate of leaf tissues must exist in some equilibrium relationship with other
substances, and that this equilibrium is to some extent reversed under the
conditions of culture in darkness. The phenomenon has not yet been ob-
served during culture in light.

The following have served as assistants in the work: Dr. Alfred J. Wake-
man; Dr. Rebecca B. Hubbell; Luva Francis, secretary.

PALEOGRAPHY

Lowe, E. A., Institute for Advanced Study, Princeton, New Jersey. Collec-
tion and study of palceo graphical material required for extension of
researches upon which he was engaged as a former staff member of the
Institution. (For previous reports see Year Books Nos. 9-35.)

The main task of the past year has been the completion of volume III
of Codices latini antiquiores, which deals with the manuscripts preserved
in Italian libraries from Ancona to Novara. Progress has also been made
with the bibliography of volume IV, which illustrates manuscripts in the
remaining Italian libraries from Perugia to Zara. During September and
October of last year field work was done in Cava, Naples, Monte Cassino,
Rome, Florence, Brescia, Milan, and Ivrea. During the winter months, the
work of editing and revising was done at Princeton; during the spring and
summer of this year it was continued at Oxford, where most of the proof-
reading was accomplished. Volume III is entirely in press save for the
preface. Some difficulty has been encountered in obtaining certain nega-
tives and this circumstance has caused delay in finishing the collotype
plates. However, all the necessary photographs will be procured during
the forthcoming Italian journey in September. Once work on the collotypes
can be continued, publication should be possible within the current year.
Volume III will have the distinction of giving the first exact reproductions
of the charred Herculaneum papyri, which were heretofore known only from
facsimiles based on hand drawings. One of the most famous of these papyri
contains an anonymous poem on the Battle of Actium. The date of the
papyrus is thus fixed between 31 B.C., when the battle took place, and
A.D. 79, the eruption of Vesuvius. The papyrus is thus a landmark in Latin
palaeography. Volume III will also have a particular interest for the student
of ancient libraries, as it throws considerable light on the oldest collection
of the Irish monastic foundation of St. Columban at Bobbio in North Italy.
At the same time with the preparation of the two Italian volumes, steady
progress has been made in examining and describing the manuscripts of
Switzerland, Austria, Holland, and Belgium, which will be dealt with in
subsequent volumes. This report would be incomplete without mention of
the writer's sincere sense of obligation to the librarians who helped him
so generously and to the staff and officers of the Clarendon Press for their
constant cooperation.

339

PALEONTOLOGY, EARLY MAN, AND
HISTORICAL GEOLOGY

Merriam, John C, and Associates. Continuation of palceontological re-
searches. (For previous reports see Year Books Nos. 20-36.)

The program of research followed in recent years has been based upon
development of a series of projects furnishing clearly verifiable data on prob-
lems having critical importance in the attempt to secure a connected history
of life in western North America. Certain of the questions investigated are
of world interest, and it is essential that we secure adequate data from all of
the points of view which can be considered with profit: such are problems
concerning the story of early man in America, the sequence of Tertiary
mammalian faunas, and the beginnings of geological history as investigated
at the Grand Canyon.

Much of the work done on all of the questions investigated has been carried
forward by individuals, cooperating on these projects either by reason of
desire to secure data bearing upon certain special situations with which they
have been concerned, or because of interest in a wider vision of major prob-
lems. Much of the time of Mr. Merriam has been devoted to planning the
modes of approach to new fields investigated or to correlation and interpre-
tation of data secured.

The amount of factual material secured and made of record is very large,
and much of value will come from further working over of the data obtained.
The contribution toward understanding of many critical questions is being
furthered by correlation of information, and especially by carrying the
inquiry regarding many questions for which additional facts are needed into
fields where answers might be furnished by examination of original mate-
rials in their natural setting.

In study of certain large groups of problems effort has been made to secure
protection for original materials, or sites, or exposures in such manner as to
open the way for further investigation in the future by students on related
questions. In this connection it has proved possible in some cases to consider
also the broader educational values available for public use.

Groups of exposures illustrating many of the types of problems to which
reference has been made are found either in the large series of formations
representing the division of later geological time known as the Cenozoic as
seen in the John Day region of eastern Oregon, or in the long series of forma-
tions exposed in the Grand Canyon of the Colorado River. In both regions
continuing study by specialists furnishes large return of new materials, while
correlation of data adds much to our understanding of fundamental values
in palseontological and geological history. In both regions it has also proved
possible so to develop the work as to make significant addition to the mate-
rials of value for purposes of general education, both of investigators and of
the lay public. Especially significant advance has been possible in eastern
Oregon, where the Oregon State Parks Commission has secured a number of
the most important sites for dedication to public use under adequate super-
vision.

340

PALEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 341

The reports following, prepared by specialists in various fields, represent
a wide range of interests but all touch in various ways the special and gen-
eral questions to which reference has been made. The work done in study
of problems concerning early man in America by L. S. Cressman, of the Uni-
versity of Oregon, Malcolm J. Rogers, of the San Diego Museum, M. R.
Harrington, of the Southwest Museum, E. B. Howard, of the Academy of
Natural Sciences of Philadelphia, Chester Stock, of California Institute of
Technology, and Ernst Antevs makes wide and fundamental contribution to
understanding of this group of problems.

Researches by Dr. H. deTerra and Dr. P. Teilhard de Chardin in southern
Asia and those of Dr. G. H. R. von Koenigswald in Java represent some of
the most important advances of this generation in study of the earliest known
stages of human history.

In palaeontology of vertebrates other than man, the investigations by Dr.
Remington Kellogg, of the United States National Museum, and Dr. Chester
Stock, of California Institute of Technology, include some of the most con-
structive contributions on the history and evolution of life obtained at this
stage in development of palaeontology.

In the field of invertebrate palaeontology Dr. Horace G. Richards, of the
New Jersey State Museum, has continued his extremely careful, and increas-
ingly valuable, work on age determination and correlation of comparatively
recent molluscan faunas.

In research concerning mainly studies in the field of geology, Dr. J. P.
Buwalda, of California Institute of Technology, has continued to make defi-
nite progress in work on some of the most difficult questions in structure and
history of Coast Range and Sierra geology in California. Dr. N. E. A. Hinds,
of the University of California, has continued his fundamental studies on
the Algonkian, rocks representing the next to the oldest of the major divi-
sions of geological time.

Mr. Edwin D. McKee, naturalist of Grand Canyon National Park, has
extended his studies of Palaeozoic formations and faunas of the Grand
Canyon and has published an important work on The environment and
history of the Toroweap and Kaibab formations of northern Arizona and
southern Utah.

Dr. Ian Campbell and Dr. John H. Maxson, of California Institute of
Technology, have carried out their carefully planned journey through the
Grand Canyon by boat, and have made large contribution to our knowledge
of the oldest series of rocks in that region, and to available data on one of
the earliest chapters of earth history.

Early Man and Culture in the Northern Basin in Oregon, by L: S. Cressman

During the year a grant from the Carnegie Institution of Washington
was made for investigating the problem of early man and culture in the
Northern Basin in Oregon with special reference to Catlow Cave No. 1. This
was supplemented by an additional grant from the Research Council of the
Oregon State System of Higher Education.

Catlow Cave No. 1 is thus designated because it was the most southerly
and the first to be examined of a number of caves in Catlow Valley. The

342 CARNEGIE INSTITUTION OF WASHINGTON

valley is in Harney County, Oregon, with its southern tip about 20 miles
north of the Nevada line. It extends some 50 miles to the north from this
point. Its center lies approximately 90 miles to the south of Burns, Oregon.
The valley is the bed of an ancient lake, of the same period (Pleistocene and
Pluvial) as Lahontan, according to Antevs.

The cave is in reality a shelter approximately 100 feet long and 60 feet
deep. It is a wave cut cave produced by wave action when the water was
at the top terrace (fourth in order from the lake bottom). Its elevation is
between 200 and 250 feet above the present valley floor.

The work has been coordinated with the work in anthropology at the
University of Oregon, and students in anthropology, especially those with a
professional interest, are taken along as workmen, thus gaining field experi-
ence. This insures an intelligent and responsible body of workmen. In
1937 we used nine students under my constant supervision and direction for
approximately six weeks, from June 22 to July 31.

Studies in the geology and geography of the valley with special reference
to drainage into and out of the valley were made by Dr. W. D. Smith, head
of the Departments of Geology and Geography, and Mr. Lloyd Ruff, in-
structor in Geology at the University of Oregon. In September Dr. Merriam
sent Dr. Ernst Antevs at my request to make further studies with special
reference to the age of the lake and the problem of stratification in the cave.
Dr. Antevs' report has been filed with Dr. Merriam and his opinion is also
given in the attached manuscript.

Skeletal remains. Parts of a human skeleton and one bone of a second were
found in gravels. Since there was no clear stratification in the cave but only
beds of different kinds of material between which the dividing lines were not
clear cut, it has proved impossible to say beyond any doubt that the deposi-
tion of the bones in the gravel was a natural process, the gravel being then
sealed over them. As the writer uncovered the bones, it seemed to him quite
beyond any doubt that they represented natural deposition with a sand and
gravel deposit of about 6 inches overlying them.

This conclusion is necessarily open to doubt in view of the character of the
beds and the shallowness of covering. In September further search under
Dr. Antevs' direction showed more bone fragments in gravels. We could not,
however, prove that they were not intrusive, as, for example, by burial.

Lack of orderly arrangement of the bones, lack of artifacts, and the scat-
tered condition of their deposition argued against burial.

The scattered character of the location of the bones argued against sec-
ondary burial. If coyotes or other animals had dug them up and scattered
them, they would have borne the marks of teeth. Doctors Hrdlicka, Hooton,
and Woodbury agree that there are no signs of gnawing, although the former
and the other two disagree widely on other characteristics of the bones.

Hrdlicka gave the cranial index as 70.2 and classified the skull as belonging
to the West Coast type. Hooton and Woodbury classified it as typical of the
well-known early Basket Maker type and said that there was nothing to
interfere with its belonging to modern antiquity. Hrdlicka classified it as
an aged female while the others agreed that it was a male specimen.

PALAEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 343

When all possibilities are examined, the one which best fits the situation
is that the body was deposited by wave action when it was in an advanced
stage of decomposition but with the bones still covered with flesh. Wave
action dismembered it and the sand and gravels covered it so that as the
flesh finally decomposed, the bones were covered with sand and gravel, giv-
ing no opportunity for gravel scratches to occur. This explanation seems to
be the most satisfactory of the possible ones.

The date, of course, cannot be fixed. If the body was deposited as has been
postulated it must have been after the lake level was in the process of lower-
ing but still high enough to break into the shelter in periods of storm. This
would probably not be more than 15,000 years ago and likely some few thou-
sand years later. It is entirely likely that we have here a representative of
early man in the New World.

Basketry. Basketry, sandals, twine, wood, and cane products were all well
preserved in the dry parts of the cave. Of these basketry alone will be dis-
cussed. This represents an excellent diagnostic type. It is a twining on a
2-ply twisted warp. Historically in baskets this type is limited to the Kla-
math-Modoc and Pit River areas. It is found in flexible bags, both his-
torically and among the Basket Makers. Archseologically, it was heretofore
known in only three fragments of baskets ; two of these were from the early
levels at Lovelock Cave ; and one was from the Columbia, of much later time,
and probably represented results of Klamath diffusion. We have archaeo-
logical specimens from caves to the west as far as Summer Lake and near
Bend. A reconnaissance party from the University has just reported speci-
mens from a cave near Heppner in the north central part of the state.
Krieger and Heizer, for the University of California, have worked over the
basketry from the Humboldt Cave, which is close to the Lovelock Cave,
and report that this type of basketry was found there.

The basketry has two values: first, it helps tie in our materials with the
Lovelock and Humboldt Cave specimens, thus assisting in fixing a time ele-
ment to ours; and secondly, it suggests that the Klamath-Modoc culture is
probably but a residuum of a lacustrine culture extending throughout the
vast area of southern Oregon when the now dry valleys were great life-sus-
taining lakes.

The basketry in the dry south end of the cave goes well back toward the
bottom, while a graver and a sandal fragment were found separated from
water-smoothed bed rock by less than a half inch of soil.

Projectiles. Arrows and in all likelihood atlatl shafts were found. No cer-
tain bows or atlatls were found. Our decision concerning atlatl shafts is
based upon the diameter of the fragments and the size of the points. Of
course these can never be decisive diagnostic evidence, but when compared
with the variations in size of other shaft fragments and points they may be
significant.

Net. A small net (about 2 feet square) was found and separately a circle of
twig 3 to 4 inches in diameter. This is very like the snare pictured and de-
scribed by Kidder and Guernsey from the Basket Maker cave in Utah ex-
cavated by Nusbaum. It is mentioned here because of its possible affiliation.
The specimens came from the upper levels.

344 CARNEGIE INSTITUTION OF WASHINGTON

Pottery. Several small fragments of pottery were found near the surface.
These so far lack cultural significance. Griffin of the University of Michigan
Museum wrote recently after examination of the specimens that they are
more suggestive of the Dismal River type from Nebraska than any other.
This is, however, only a suggestion.

Thirty miles north of Catlow Cave No. 1 is Roaring Springs Cave, which
was examined hastily last summer. This promises to provide better and
more numerous artifacts than Catlow Cave No. 1. It is drier than the other
cave, so the contents are better preserved. The excavation of this cave will
be the first work of this summer's field party (1938) .

We shall also do further digging in Catlow Cave No. 1 to discover, if
possible, more skeletal remains.

It is important that our work should at the first opportunity be pushed
east of Steens Mountain and across Malheur County toward Idaho. The
second part of the field season this summer will be devoted to excavation of
caves in the Summer Lake region close to Paisley and near Fort Rock.

Archaeological and Geological Investigations of the Cultural Levels in an Old
Channel of San Dieguito Valley, by Malcolm J. Rogers

With support from a grant by the Carnegie Corporation of New York
to the Carnegie Institution of Washington, it has been possible for Mal-
colm J. Rogers, Chief Curator of the San Diego Museum, to organize a
field expedition and undertake excavation in the San Dieguito River Valley
for the purpose of cultural studies. The site chosen seemed to offer the
deepest accumulation of alluvium available, and when the trench was com-
pleted, it was found to have been a fortunate choice, for a complete record
of post-pluvial river history was uncovered. In addition to this the expedi-
tion was fortunate in intercepting certain unexpected archaeological features.

In sinking the trench the ground was taken out in horizontal strips and,
beginning at the top, after going through 2 to 3 feet of recent flood silts,
a Yuman camp level with a maximum depth of 2% feet was uncovered.
This had been built upon 3 feet of lateral outwash soil of terrestrial origin.
Under this was encountered a 2-foot band of boulders and sand deposited
during a period of flash flooding. Beneath this was a stratum, 2 feet in
thickness, which was of stream origin. It consisted of coarse sands and
yellow, clayish sands. The lowest stratum was composed of boulders and
sand strata which attained a thickness of 7 feet at the entrance of the
trench. This formation rested on a Tertiary sandstone into which a
Pleistocene channel had been cut.

The lowest stratum was also implementiferous, and most cultural material
consisted either of factory debris or of transported items. In the upper
third, however, was found a degraded camp level which produced many
whole implements. This streak was followed laterally both ways until
cave-ins made it too dangerous to do further work. Stream-transported
implements occurred to the very base of the stratum and on the contact
with the Tertiary surface. These are probably Phase I or II San Dieguito
tools derived from camps farther up stream. The camp level matter is all

PALEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 345

Phase III material, as well as that found in the corresponding horizon in
mid-channel residual humps.

Splendid examples of solifluction were found throughout the main trench
section, probably the first found in the New World. San Dieguito imple-
ments were even found on top of the Yuman horizon, being the result of
lateral outwash.

Researches of M. R. Harrington

During the period July 1, 1937 to June 30, 1938, one research project was
undertaken with funds made available by the Carnegie Institution of Wash-
ington. This was an archaeological reconnaissance in Lake County, Cali-
fornia, to investigate a report that Folsom projectile points had been dis-
covered on a certain site in Clear Lake Park and that other known types
of early stone implements had been found in the vicinity. The report was
made by Mr. Chester C. Post, retired merchant and amateur archaeologist
of Berkeley, California, a member of the Southwest Museum, Los Angeles.

The month of April 1938 was spent in this investigation by Mr. M. R.
Harrington of the Southwest Museum, with Mr. S. M. Wheeler as assistant,
aided by the volunteer services of Mr. and Mrs. Post, and for a short time
by Mr. Elden Baylard, a local man employed as laborer.

The region of Clear Lake, in Lake County, is of volcanic origin, with one
large extinct volcano, Mount Konocti, rising nearly 3000 feet from the
southwestern shore, and a number of obsidian deposits, especially near the
southeast end of the lake. Most of these have been worked by ancient
peoples from remote prehistoric times. Clear Lake is nearly 20 miles long
and its waters are fresh and potable.

Archaeologically the country is very rich, and private collections are
numerous. An inspection of these revealed a number of types of implements
varying greatly in form, finish, and degree of patination, suggesting the
presence of different cultures in the district at various times. An archaeo-
logical study of the whole region, working back from known historic village
sites of the present Pomo Indians, should prove of great interest and might
establish a guide to the sequence of cultures in northern California.

Although the collections contain a few points that suggest Folsom styles,
true Folsom points were seen only among the material collected by Mr. Post
on the site he reported, situated on Borax Lake in Clear Lake Park. There
are six of these, including one perfect specimen of yellow chalcedony. The
others are all obsidian.

Borax "Lake" is a lake bed situated in a landlocked basin, possibly an old
crater, among the hills about half a mile northeast of the southeast end of
Clear Lake. At the present time the water, very saline, remains only in the
northwest end; but it is plain that at one time it stood at a considerably
higher level. The lake bed is about 1% miles long by V2 mile wide. The
site is situated on a low terrace just east of the southeast, or dry, end of the
lake bed, above the level of the highest traceable former shore line of the
lake.

346 CARNEGIE INSTITUTION OF WASHINGTON

A young walnut grove occupies the site, and the ground had been recently
plowed, exposing an area of blackened soil, roughly 300 feet in diameter,
strewn with flakes and fragments of obsidian and other materials used by
the former inhabitants. A careful search of the surface revealed three more
typical Folsom points, together with scrapers, gravers, and other implements
constituting almost the entire Folsom complex of Roberts. In addition to
these were many points and other objects characteristic of the Lake Mohave
complex as published by the Campbells, including both Silver Lake and
Lake Mohave types, and a form of wide-shouldered, narrow-stemmed point
we have named the "Borax Lake" type. This, reported only sporadically
elsewhere, seems especially abundant on this site.

A few small test holes with a trowel revealed the fact that human indi-
cations continued quite a distance below the surface; and realizing the
importance of a site containing Folsom artifacts on the surface, we decided
upon a trial trench. Obtaining permission from Captain Harry Wallis,
manager of Clear Lake Park, we started our trench between two rows of
walnut trees in the middle of the area that had yielded the largest number
of Folsom points. This trench, 6 feet wide, was divided into yard squares
for convenience in recording. By the end of April we had excavated, with
small trowels, 30 feet of this trench, running from 7 to 8.5 feet in depth, with
tests down to 10 feet, and had found underground 251 artifacts, exclusive
of chips and flakes.

We found that the black soil containing most of the artifacts ran about
5 feet 4 inches deep; below this flakes of obsidian and occasional artifacts
continued down to more than 8 feet in places, mixed with the yellow subsoil.

To summarize briefly our results: Strictly Folsom objects were found
only on the surface, although certain types of scrapers that are common to
both Folsom and Lake Mohave did appear underground. Moreover, Silver
Lake points and other objects belonging to the Lake Mohave but not to the
Folsom series were also found below the surface. No projectile points of
any kind appeared below 40 inches, except the base of a Folsom-like form
at 59 inches, which may have reached its resting place through a rodent-
or root-hole from above. A crude metate appeared at 56 inches; a short
cylindrical pestle-like implement was found at 35 inches, and a mortar
fragment was unearthed at 46 inches, in the bottom of a disturbed area.
In the lower levels a few heavy scrapers and choppers were found.

Our tentative conclusions, based on the small amount of work done, may
be stated as follows:

A. People of the Folsom culture visited the Borax Lake site and camped
thereon, presumably about the same time as the Folsom occurrences in New
Mexico and Colorado, where we know they were associated with mammals
of Pleistocene type, now extinct.

B. Previous to the arrival of the Folsom people, the Borax Lake site had
been inhabited long enough to accumulate gradually more than eight feet
of soil mixed with human artifacts.

C. On this site the Lake Mohave and Borax Lake cultures are older than
Folsom, but continued until the arrival of the Folsom people; in short they
are both earlier than and contemporary with the Folsom culture.

PALEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 347

D. The crude grinding slab or metate and the short cylindrical pestle are
older than Folsom on this site.

E. The crude bowl-shaped mortar may be older than Folsom, but its
relation to the deposits on this site is uncertain.

F. Massive choppers and scrapers appearing in the lower levels of the
deposit may represent a culture older than Folsom, Lake Mohave, or Silver
Lake.

As mentioned, the above conclusions; are tentative only. A great deal
more of careful stratigraphic work is needed on this important site before
final conclusions can be made.

Researches of E. B. Howard

In the course of one of Dr. Merriam's recent trips to St. Augustine he had
an opportunity to examine some fossil vertebrate material which was on
display at the filling station of a Mr. Ed Johnson at Bon Terra, St. John
County, Florida, about 29 miles south of St. Augustine just off the shore road.

Believing that there might be some association of these vertebrates with
man, Dr. Merriam asked the writer to investigate the site a little further.
This he did in February in company with Mr. Malcolm Lloyd of Phila-
delphia.

Unfortunately it had been raining heavily for several days before and
during the time we visited the site, so that the place from which the bones
had come was completely covered with water. The site is a low field between
the road and the Inland Waterway Canal. The field is about V4 mile wide
at the point where the bones were found by one of Mr. Johnson's sons, who
has since died.

The site is apparently the same general locality mentioned by Hay,1
from which a collection had been made by a Mr. Fred R. Allen some years
ago. Hay mentions the following specimens in the collection: Mammut
americanum, Equus sp., Mylodon harlani, Terrapene antipex, Elephas co-
lumbi, all of which he regarded as belonging to "some part of the first half of
the Pleistocene, probably the first interglacial."

The site from which Johnson secured his material is in about the middle
of the marshy field, which is composed of muck resting on a grayish sand
which in turn rests on a coquina. It was too wet to do more than probe
around the hole left by the previous digging, and the result was that no proper
investigation could be made. The specimens which Johnson is said to have
dug from this spot, and which were on exhibit at the filling station, included
ground sloth, mastodon, mammoth, horse, tapir, and camel. There was also
from the same place an object that resembled a bone awl, but which turned
out not to be an artifact. Whether it was the spine of some fish or other
form from the sea could not be determined.

The site appears to be a continuation north of the Melbourne and Vero
beds, and the faunal assemblage seems to be much the same. It would be
worth while to make a further investigation at some time during a dry season.

1 Oliver P. Hay, The Pleistocene of North America and its vertebrated animals from the
states east of the Mississippi River and from the Canadian provinces east of longitude 95°.
Carnegie Inst. Wash. Pub. No. 322 (1923).

348 CARNEGIE INSTITUTION OF WASHINGTON

Studies on the Climate in Relation to Early Man in the Southwest, by Ernst

Antevs

These studies brought important results during the past year.

In the summer of 1937 an unusually heavy flood of the Whitewater Wash
in the southeastern corner of Arizona deepened and widened the arroyo,
exposing new profiles, many bones of extinct mammals, and several buried
sites of the Cochise culture. The fossil bones represent chiefly mammoth,
sloth, dire wolf, horse, and bison, all extinct. These bones are sufficiently
numerous and important to induce Dr. Chester Stock to plan a collecting
trip to the Whitewater arroyo this fall (1938).

The Cochise culture, which is studied in collaboration with the Gila
Pueblo Archeological Institution at Globe, Arizona, occurs in direct asso-
ciation with the fossil bones as well as in strata correlated with the bone-
bearing beds. It is one of the oldest records of man in North America.

Part of the charcoal found with the Cochise artifacts at the Double Adobe
site has been identified by Dr. R. W. Chaney as hickory. In our day the
nearest occurrence of hickory is some 800 miles distant in the mountains of
northeastern Mexico and in eastern Texas. In a region with high tempera-
ture and great evaporation the hickories grow in wet woods, along streams
and on the borders of swamps. Unfamiliar with the great moisture require-
ments of the hickories, the writer at first concluded that the erosion surface
underlying the artifact-bearing sand, as well as this sand itself, indicated a
dry stage, as does the modern arroyo cutting and the sand and gravel on
the arroyo floor. The presence of hickory, however, is conclusive evidence
that the climate then was subhumid to humid and that there was a perma-
nent stream in the valley. The main channel of the old stream may have
been lower than the floor of the present arroyo, the sand being a flood-plain
deposit. Therefore the artifact-bearing sand bed dates from the Pluvial
period, as does the superimposed laminated clay, which was deposited in a
permanent lakelet dammed perhaps by beavers.

Much search has been made for irrefutable field evidence of contempo-
raneity of man with the highest stand of the large Pluvial lakes of the
region, especially Lake Cochise, which occupied the Willcox basin.

The climatic variations during the postpluvial age, or the past 10,000
years, have been studied in so far as they are revealed by different kinds
of sediments and by the intercalated stages of erosion. Conditions and
fluctuations during the past 2000 years are being dated with the help of
potsherds.

Studies of Geology, Palaeontology , and Archaeology Relating to the Origin of
Man as It May Be Recorded in the Himalayan Region of Asia, by

H. deTerra

These studies have been supported in part with financial aid from the
Carnegie Corporation of New York to the Carnegie Institution of Wash-
ington.

Measuring the Age of Man in terms of cyclic geologic processes has always
been a subject fascinating to both geologists and archaeologists. Unfortu-

PALAEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 349

nately we know too little of such processes outside the glaciated regions to
work out a stratigraphic scheme which might be applied to wider areas, and
yet this would be the solution to many important problems concerning Ice
Age and prehistory of man. Following the writer's previous work in India,
it was thought that the Ice Age chronology as worked out by him in the
Himalayas might well provide us with means by which we could visualize
and measure the evolution of Stone Age man in Asia. Indeed, the geological
evidence in India had clearly pointed to a correspondence of glacial with
pluvial stages, the latter being characterized by thick, coarse-grained sedi-
ments. These previous studies had also disclosed that the Paleolithic of
India was associated with a system of terraces in which were reflected both
a climatic and a diastrophic cycle. Although no human fossils had come to
light, it was evident through thousands of stone implements, found in ter-
races and with fossils, that early man in India dated back to the second
Himalayan glaciation. This, to all appearance, represents the Mindel
glaciation of Europe. From that time on Stone Age records were traced in
India up to the appearance of the first man-built monuments, which in
Kashmir probably date back to at least 6000 B.C.

These results, which have been submitted for publication to the Carnegie
Institution, warranted a new investigation of this subject in countries lying
to the east. It was hoped that this might lead to correlations with China
and Java, where similar studies have more recently led to new discoveries
of fossil man.

The expedition of this season led to Burma and Java and lasted from
October until the end of May of this year. Once more it was possible to
obtain the cooperation of Dr. Teilhard de Chardin as palaeontologist.
This work was carried out jointly with the Carnegie Institution of Wash-
ington, the Academy of Natural Sciences at Philadelphia, and the Peabody
Museum of Harvard University. The last mentioned shared with the
American Philosophical Society the major expenses for this expedition.
Dr. H. L. Movius from the Peabody Museum at Harvard was in charge of
the archaeological work.

Under the writer's direction field work was carried out in Burma from
November 1937 until March 1938. Following this, the expedition members
proceeded via Malaya to Java, where they established contact with the
work which Dr. von Koenigswald is doing on behalf of the Carnegie Insti-
tution.

Geological and palceontological results. Our main field of investigation
lay in Upper Burma, in the Irrawaddy Valley, and in the Shan States to the
east of it. The geology of this region is similar in many respects to that of
the Himalayan foothills. As in India, the formation of terraces succeeded
the deposition of an early Pleistocene formation from which we collected a
great number of vertebrate fossils. These indicate that Burma was at that
time linked with India and South China by a great migration route of
mammals which permitted faunistic interchange between these regions and
the East Indian archipelago, which at that time was still part of the conti-
nent. In the early Pleistocene beds two phases are represented, of which
the older was a period of heavy rainfall. A second such "pluvial" stage is

350 CARNEGIE INSTITUTION OF WASHINGTON

revealed by red boulder gravels which overlie the older beds disconformably.
A third and fourth pluvial finally are recorded by younger gravel terraces
which in composition and number correspond to the terraces attributed in
India to the third and fourth glacier advances. The intervals between these
stages are indicated by erosional breaks in the terrace sequence, and espe-
cially by the formation of certain fossil soils indicating dry climatic inter-
vals.

This stratigraphic pattern of the Quaternary of Burma shows that the
northern tropical belt of Asia responded to a climatic cycle similar to that
which is known to have existed in northern latitudes. This feature opens
for the first time possibilities of covering under a single stratigraphic and
physiographic scheme the Quaternary history of the whole south and central
Asiatic mass. So far as South China is concerned, its applicability appears
to be assured by the fact that in the Yangtse Valley terraces and soil forma-
tions occur similar to those in the Indian and Burmese river tracts. Also
the highlands connecting these countries share extensively in the same fossil
records of Quaternary time, as was revealed by our expedition through cave
excavations. This uniformity of geological events during the Ice Age must
be of interest to palaeontologists and archaeologists alike. Both are dealing
with studies of ancient life which can now be visualized more clearly than
ever, as having been determined by the impacts of climate and mountain
making such as are revealed by great geographical changes in the lowlands
bordering High Asia.

Archceological results. Implements of ancient man were found at many
places in Upper Burma, chiefly in gravel terraces but also near the surface
under a slight cover of wind-blown sand. The latter has covered up tem-
porary settlements of people using polished stone tools and handmade pot-
tery. The older gravels contain locally great numbers of crude stone tools ;
most of them are waterworn, and yet in some cases they are associated with
their contemporary fauna, which is of middle Pleistocene age. In some
respects these artifacts resemble the Indian "Soan cultures," which are char-
acterized by the absence of hand axes. But the Burmese Paleolithic is much
cruder in workmanship than the Indian ; for one thing, it lacks any associa-
tion with hand axes. This and other significant typological features appear
to connect it with the oldest Chinese culture of Choukoutien as well as with
the Old Paleolithic of Java. It is obvious that such archaeological relation-
ships reflect a new Paleolithic tool complex different from anything which
either Europe or Africa has to offer. But it is to be noted here that the
Folsom culture of North America has its typologic parallels with this south-
east Asiatic Paleolithic. It seems therefore that Burma was situated near a
center of dispersal from which Old Paleolithic cultures migrated during the
middle and upper Pleistocene. Some 250,000 to 350,000 years ago Burma
lay within a cultural circle of extinct races which to all appearance did not
belong to the Peking-Java Man stock but to a very early Neanderthaloid
species.

Such a conclusion was reached only after we had visited Java. Here, we
had the most welcome chance to study at close range the geological and

PALAEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 351

palseontological problems connected with the famous fossils of extinct man.
With Dr. von Koenigswald as a guide we could not fail to appreciate the
work that is being done by him and his Dutch colleagues. In view of the
association of certain Paleolithic tools found here with the Neanderthaloid
Solo Man, and considering the absence of implements in the Trinil beds
which contain the remains of Java Man, it would seem as if the Old Paleo-
lithic is here not to be connected with the most ancient human fossils.
Another result of our visit was the recognition of certain geological features
in the Quaternary of Java which make correlations with the mainland of
Asia less readily available than was at first anticipated.

European study tour. In view of the new information received from these
Asiatic studies it seemed imperative to compare certain outstanding strati-
graphic and archaeological features with records of early man in Europe.
An opportunity presented itself for a study tour which led to the classic
region of the Somme Valley in France, to the Rhine Valley, and to various
sites in Germany where the geological data are especially clear. The general
impression received from these studies was that in central Europe the
geological dating of early human remains is greatly hampered by the fact
that most of them are found away outside the glaciated tracts, where
terraces or gravel deposits cannot be readily connected with the ice advances.
This introduces an element of uncertainty inasmuch as the palseontological
method of stratigraphy is by itself insufficient for dating purposes. A closer
tie with the glacial cycle is required, and this could be achieved only if
detailed inquiries were made in areas where Alpine or continental glaciers
have left their records. Despite the extensive work that has so far been
done in central Europe, it would seem that here lie research fields of a very
promising nature.

Anthropological and Historical Studies Relating to the Earliest Evidence of

Man, by G. H. R. von Koenigswald

These studies have been supported with financial aid from the Carnegie
Corporation of New York to the Carnegie Institution of Washington.

The researches on the lower Pleistocene Djetis and the middle Pleistocene
Trinil fauna have been continued. A large collection of fossils from these
layers has been made, especially from the area north of Solo, and a remark-
able number of species new to these faunas has been found, especially of
rodents (Lepus 2, Rhizomys 1, Rattus 1) and carnivores {Canis 2, Ursus cf.
malayanus and U. cf. kokeni, Viverricula 1, Paradoxurus 1, cf. Herpestes 2,
div. spec, indet.). Furthermore, we found Tragulus and a new species of a
big antelope, and a number of fine teeth of Hylobates and Simia. Some of
the new species seem to be identical with species from southern China, and
the new finds prove more than we expected the influence of the Chinese
"Sinomalayan" fauna.

The most important finds are remains of Pithecanthropus, of which a skull
cap and a mandible were mentioned in the last report. In addition, a few
isolated teeth have been found (not yet described), some of them unworn
and in perfect condition. A big upper molar shows traces of an accessory

352 CARNEGIE INSTITUTION OF WASHINGTON

cusp near the protocone, a feature also observed in Sinanthropus and Aus-
tralopithecus. The crown pattern of unworn lower molars resembles much
those of Sinanthropus except that the wrinkles are less complicated. But in
the Pithecanthropus teeth the entoconid seem to be less developed, so there
is no important difference between these and the corresponding teeth of an
anthropoid.

The Modjokerto area, visited twice, has yielded no special new finds. In
the Southern Mountains (Goenoeng Kidoel) more palaeolithic stone imple-
ments have been collected, bringing up the whole collection to more than
3000 specimens. In the rock fissures more teeth of anthropoids {Simia, Sym-
phalangy, Hylobates) have been found, and traces of a large tapir (cf.
Megatapirus augustus Matthew and Granger, from southern China).

A special research for stone implements has been made on the old river
terraces along the Solo River north of Ngawi. A few primitive implements
have been collected, but these upper Pleistocene gravels have yielded no
hand axes.

D. P. Erdbrink has discovered a new area with palaeolithic implements
south of Soekaboemi, western Java, of which we made a good collection.

In February, after the Prehistoric Congress held in Singapore, a trip was
made through Malakka and Siam to continue the research on fossil mammals
from the Chinese drug stores. Interesting material of the Pontian Hip-
parion fauna (including Hycenarctos and a big Anchitherium) and of the
Pleistocene cave fauna (fossil orang; two teeth of fossil man) could be
acquired.

In April Dr. H. deTerra, Dr. Teilhard de Chardin, and Dr. H. Movius
visited Java. A joint excursion through Java was made, especially to the
sites where fossil man has been found, and to the sections which show the
stratigraphical sequence. In July Professor A. Heim-Zurich visited the new
Pithecanthropus site.

In collaboration with Dr. H. Movius (Harvard University) the palaeo-
lithic culture of Patjitan will be described.

Researches of Remington Kellogg

In connection with studies now in progress on the cetotheres, the precursors
of the living whalebone whales, the types of nearly all the known Tertiary
forms have been critically examined. Additional cetothere material, repre-
senting several different types, has been obtained during the past year from
the Miocene Calvert formation in Maryland and Virginia. Nevertheless, the
available material is still inadequate for detailed studies on the skeletal con-
struction of some of these extinct whales. It is expected that continued field
work will supply the necessary material. During the past year cetotheres
described by E. D. Cope have been loaned to the writer for study by the
Academy of Natural Sciences of Philadelphia and the American Museum
of Natural History. In the interim between the Preliminary Whaling Con-
ference held at Oslo, Norway, in May, and the International Conference for
the Regulation of Whaling held at London, England, during June 1938, fossil,
subfossil, and Recent cetacean material was examined at Stockholm, Uppsala,
Copenhagen, Sandefjord, Bergen, London, and Edinburgh.

PALAEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 353

Since one of the objects of these palaeontological studies has been to eluci-
date how the characteristic skeletal and cranial peculiarities of the several
families of whalebone whales were acquired, each structural condition has
been examined in the light of the existing knowledge of the successive types
that have made their appearance in the course of geologic time and of the
progressive ontogenetic changes that can be observed in fetal skulls of
mysticetes. A cursory examination of these cetothere skulls demonstrates
that the original relations of the bones that comprise the braincase have
been altered by the slipping of one bone over another, but more precise
studies are required to discover the factors involved in this evolutionary
process whereby the skulls of the members of the several lines of develop-
ment represented among the whalebone whales have been remodeled in
different directions. By employing a pantograph it has been possible to
obtain true orthographic projections of the cranial architecture of these
cetothere skulls. Since these are all drawn to the same scale, it has facili-
tated examination of the directions in which the skulls of these cetotheres
have been altered by this telescoping process. Detailed comparisons of the
skeletal and cranial peculiarities of these cetotheres have demonstrated the
importance of an adequate series of fetal skulls of Recent whalebone whales
for the interpretation of puzzling structural conditions. Through the active
cooperation of the United States Coast Guard whaling inspectors, Mr. Marc
Lagen, manager of the American Pacific Whaling Company's stations in
Alaska, and the officials of the Western Operating Company's antarctic
floating factory Ulysses, additional material of considerable importance to
these cetacean studies has been acquired by the United States National
Museum, including the fetuses of several whalebone whales, and a skull of
the antarctic right whale. Illustrations for some of this cetothere material
have been made by Mr. Sydney Prentice.

Researches of Chester Stock

During the past year Carnegie Institution of Washington Publication
No. 487 has been completed with the printing of four reports in addition
to those indicated in the Year Book for 1937. These articles are listed in
the bibliography.

Among studies of Tertiary mammalian faunas and horizons of western
North America are listed investigations now complete or nearing completion.
Paul C. Henshaw has completed his study of a late Miocene or early Plio-
cene mammalian fauna from the Avawatz Mountains, San Bernardino
County, California. Among the several faunal stages known from the
Mohave Desert area, this assemblage appears to be most closely related
to the Ricardo. The significance of the Avawatz fauna lies largely in the
fact that it aids in establishing the age of some important diastrophic
events in this section of the Mohave Desert, south of Death Valley. Mr.
Henshaw's report is being submitted to the Institution for publication. A
study of the fossil rodents in the Avawatz fauna by Dr. R. W. Wilson is
now under way. J. F. Dougherty has completed a study of the skull and
skeletal material of Paratylopus cameloides from the John Day deposits

354 CARNEGIE INSTITUTION OF WASHINGTON

of eastern Oregon. This paper and one by Chester Stock on complete
Hipparion remains from the Thousand Creek beds, Nevada, will be sub-
mitted shortly for publication.

The Central Washington College of Education at Ellensburg, Washing-
ton, was visited this year and through courtesy of Professor G. F. Beck
the important collections of fossil mammals from the Ellensburg and
Ringold formations were examined. Opportunity was also afforded to see
the occurrence of some of this material in the field. Age of the Ellensburg
and Ringold formations has been under discussion for some years and
determination of the age of the Ellensburg is of special interest to students
of the Tertiary geology of eastern Oregon and eastern Washington in view
of the relationship of the Ellensburg to the Columbia lavas.

Studies relating to the Quaternary period include continuation of the
detailed investigation of the fauna obtained in Pit 10, in which human
remains are known to occur, at Rancho La Brea. The report on the birds
in this assemblage by Dr. Hildegarde Howard and Dr. Alden Miller is
practically complete. Examination of the mammalian fauna has focused
attention upon the Canidse of Rancho La Brea. It was found necessary to
review in detail the Pleistocene Canidse to establish a basis on which the
characters of the dogs in the Pit 10 assemblage might be properly evaluated.
This survey brought to light a number of skulls of the timber wolf, not
heretofore recognized as occurring in the Los Angeles Museum collections.
The material furnishes valuable information which was not available to
J. C. Merriam when he published his memoir on the Canidse of the brea
deposits in 1912. A survey of the Pleistocene coyotes from Rancho La
Brea has made available a single jaw of unique character. This was de-
scribed by Chester Stock.1

At the request of Harold Gladwin and E. B. Sayles, the Gila Pueblo at
Globe, Arizona, was visited to examine a collection of mammalian remains
obtained by the Gila Pueblo in the course of excavations in southeastern
Arizona. The mammalian materials come from deposits containing a human
record and it is, therefore, of significance to determine the relationship of this
assemblage to known mammalian faunas of the later Quaternary in the
Southwest. Opportunity was afforded to discuss the nature of the occur-
rence and the climatic implications with Dr. Ernst Antevs. Plans were laid
for an examination of the field relationships and for further collecting of
mammalian remains in the Quaternary desposits of Sulphur Springs Valley,
Arizona.

At the request of Dr. Merriam two visits were made to the site of the San
Dieguito culture, which is being investigated by Malcolm Rogers of the
San Diego Museum. Opportunity was afforded to discuss with Mr. Rogers
the problem of early man as presented by the excavations and the results
obtained at the San Dieguito River localities.

On July 31, 1938, John L. Ridgway retired from active duty as scientific
illustrator for the Carnegie Institution of Washington and the California
Institute of Technology. A tribute to Mr. Ridgway has been published else-

1 Chester Stock, Bull. Southern Calif. Acad. Sci., vol. 37, pp. 49-51, pi. 10 (1938).

PALAEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 355

where.1 Mr. Ridgway's career has been a long and distinguished one. He
was early associated with the Carnegie Institution as adviser in matters of
illustration. During the past eighteen years he has been in the employ of
the Institution as scientific illustrator and in this period has been responsible
not only for countless numbers of drawings, but also for the high standards
of illustration shown in the palseontological papers and monographs pub-
lished particularly by the Institution. His recently published book, Sci-
entific illustration (Stanford University Press, 1938), should find wide use
among authors and others interested in the creation and reproduction of fine
illustrations. David P. Willoughby is now employed as scientific illustrator.

Studies on Pleistocene Mollusks, by Horace G. Richards

Three reports have been prepared which are based upon field work made
possible by previous grants from the Carnegie Institution of Washington
(see bibliography) :

1. A preliminary report has been written in collaboration with Professor
B. F. Howell, of Princeton University, on the Pleistocene of the Champlain
Sea of Vermont. Eight species of mollusks were recorded.

2. A report has been prepared on the Pleistocene fresh-water mollusks of
Louisiana and Mississippi. The field work for this report was completed
in September 1936, and was carried on in cooperation with some work done
under the auspices of the Geological Society of America. The report lists
twenty-three species from seven localities.

3. The final report on the marine Pleistocene of Florida has been pub-
lished. This work was aided jointly by the Carnegie Institution and the
Geological Society of America.

With the aid of an additional small grant from the Carnegie Institution,
the writer has been able to continue his studies on Pleistocene mollusks
during 1938. Much of this work has been done at the Academy of Natural
Sciences of Philadelphia. In addition to the studies on material which the
writer had personally collected on previous occasions, he was able to devote
some time to several small collections which had been sent to him for deter-
mination. Several of these collections had been taken from archaeological
sites and it is hoped that the study of the shells may help in the dating of
the respective sites. The complete results will appear elsewhere ; the follow-
ing is a summary of the most important collections studied:

A large collection of Pleistocene marine mollusks from North Creek,
Florida, collected by the writer in 1937, was studied. A correlation with
the Pamlico formation is suggested.

Pleistocene mollusks from the Gulf Coast of Texas collected by Dr. W.
Armstrong Price and the writer in 1936, 1937 and 1938 were studied. The
dating and correlation of the material is discussed in a report to be submitted
to the Geological Society of America.

A small collection of land and fresh-water shells submitted by Dr. Ernst
Antevs from archaeological sites in southern Arizona included the following:
Helisoma trivolvis (Say), Succinea avara Say, S. grosvenori Lea, Lymnma
palustris nuttaliana Lea, L. caperata Say, L. obrussa Say (?), and Sphcerium

1 Chester Stock, Science, vol. 88, pp. 145-146 (1938).

356 CARNEGIE INSTITUTION OF WASHINGTON

aureum Prime. All the species are to be found living in the same vicinity
today.

A collection of shells was submitted by the Missouri Resources Museum
(Jefferson City, Missouri) from an archaeological site in a cave near Scotia,
Crawford County, Missouri. The following were identified: Polygyra zaleta
Binney, P. inflecta Say, P. appressa Say, P. monodon cava Pilsbry and
Vanatta, P. profunda Say, P. elevata Say, Anguispira alternata Say, Lymno&a
obrussa Say, Campeloma subsolidum Anthony, and Sphcerium striatinum
Lamarck. Since all these species are known to be living in Missouri today,
a recent age is suggested for the site.

A collection of shells from Irene Indian Mound near Savannah, Georgia,
was studied. The material was submitted by Dr. V. J. Fewkes, Supervisor
of the Irene Mound W.P.A. Project. Marine, brackish, and fresh-water
species were included. A report is to be submitted to the Irene Mound
Project.

The Pleistocene mollusks obtained by Dr. Richard F. Flint on the Boyd
Arctic Expedition to Greenland in 1937 were submitted to the writer for
study. The material contains only ten species and is apparently of late
Wisconsin or post-Wisconsin age. A comparison of these shells with material
collected by Captain Bob Bartlett from the Recent seas off northern Green-
land suggests that the Pleistocene mollusks lived in somewhat less saline
waters. A brief statement on the collection has been submitted to Dr. Flint
for inclusion in his report on the geological results of the expedition.

The study of a small collection of fossils from Pleistocene deposits on
Castor River, 15 miles north of Hawk Bay, Newfoundland, collected by Dr.
Girard Wheeler of Rutgers University (New Brunswick, New Jersey) added
Serripes groenlandica Beck and Buccinum tenue Gray to the list of Pleisto-
cene mollusks from Newfoundland.

A collection of marine shells from a Maya burial near Chichen Itza, Yuca-
tan, submitted by Mr. H. J. Boekelman of the Louisiana State Museum,
contained the following: Polinices duplicata Say, Crepidula fornicata Linne,
Modulus modulus Linne, Neritina virginea Linne, Oliva sayana Ravenel,
Olivella nivea Gmelin, Marginella apicina Menke, M. labiata Val., Thais
hcemastoma floridana Conrad, Cerithium muscarum Say, Littorina anguilijera
Lamarck, Vermicularia spirata Philippi, Fasciolaria tulipa Linne, Colum-
bella mercatoria Linne, Conus sticticus Adams, Cantharus cancellaria Con-
rad, Chione cancellata Linne, Area occidentalis Philippi, Chama sp., Anom-
alocardia cuneimeris Conrad, Rangia flexuosa Conrad, Cardita floridana
Conrad, Mytilus exustus Linne, Pedalion alata Gmelin.

Researches of J. P. Buwalda

The mapping and study of the complex fault system bounding the San
Gabriel Range on the south was extended somewhat farther eastward from
the Mount Wilson section of the range, and the relation of the Raymond
fault, which bounds the Pasadena block on the south, to the main fault
system in the area where it joins that system was more clearly defined.
Owing to the large accumulation of erosional waste swept out of the canyons
of the mountain front and deposited as alluvial fans along the base, the

PALAEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 357

attitudes and structural relations of the individual faults are usually dif-
ficult to determine, but the fault pattern is very significant with reference
to the question of horizontal or strike-slip displacement, touched upon in
an earlier report. Most of the persistent and long faults of southern Cali-
fornia, especially those that trend northwest-southeast, have experienced
extensive horizontal movement. The fault system along the south face of
the San Gabriel Range has clearly suffered large vertical or dip-slip dis-
placement. The absence of important horizontal dislocation, previously
inferred, is very fully corroborated by more recent work. The pattern, in
addition to being very complex, contains many important faults which
make large angles with the trend of the system, contrasting with the general
linearity or near parallelism of the component faults in the strike-slip
fault zones. Locally the entire fault system along the base of the range
turns abruptly, giving rise to strong salients and recesses in the front.
The pattern therefore seems scarcely to admit of important horizontal dis-
placement. The Raymond fault joins the main system not in a clean junc-
tion but in a zone of subparallel faults rather widely spaced, some of the
blocks in which have been uplifted some distance with the main San Gabriel
block and well above the San Gabriel Valley to the south. The pattern
of the Raymond fault likewise involves sharp-angle deviations and striking
salients, and it likewise is difficult to interpret as other than a dominantly
dip-slip fault of reverse character on which the horizontal displacement,
if any, has been so inconsiderable as not to affect the fault pattern. The
conclusion that some of the active faults of southern California are expe-
riencing entirely different types of dislocation from those which have usually
been regarded as the more active and more culpable in originating earth-
quakes has an important bearing on the whole question of the mechanics
of the deformation of the region and the actual genesis of the recurrent
shocks.

Several years ago, at the suggestion of Dr. Arthur L. Day, several experi-
ments testing geophysical methods for determining crustal structure were
performed and the results published. In the course of this study, in collab-
oration with Dr. B. Gutenberg and Mr. H. 0. Wood, velocity of seismic
waves in the granites of the Yosemite region was measured, the investiga-
tion being supported with funds made available by the Carnegie Institution
of Washington. In continuation of this study, through the encouragement
largely of President Merriam and his interest in expanding our knowledge
of the superb natural features of Yosemite Valley, an investigation was
begun to determine the thickness of the alluvial fill in the valley and there-
from the actual form of the bedrock trough excavated by the glaciers which
now constitutes the valley. This research, supported largely by the Geo-
logical Society of America but also in part with funds and equipment con-
tributed by the Institution, was completed in the field in September 1937,
and the results are now nearing completion for publication. This seismic
reflection mode of attack revealed the rather astounding fact that the depth
of the alluvial fill in the portion of the valley near the government head-
quarters reached a maximum of nearly or quite 2000 feet, indicating that
the depth of the valley seen by the visitor to the Park, about 3000 feet,
is actually only about three-fifths of the real depth of the glacial trough.

358 CARNEGIE INSTITUTION OF WASHINGTON

A second surprising fact discovered is that the floor of this trough appears
to rise about 1000 feet in going downstream some 3 miles from near the
government headquarters and Camp Curry to the neighborhood of El
Capitan. It appears also that the fill in the valley is not a single unit, but
consists of three bodies of material possessing quite distinct velocities of
transmission for the dynamite- generated artificial earthquake waves utilized
in this type of geophysical investigation.

Researches on Algonkian Formations, by Norman E. A. Hinds

During April 1938, a brief trip was made to southeastern California for
the purpose of further studying Algonkian deposits in the desert ranges
southeast of Death Valley. This series of sediments very possibly was once
continuous with that at Grand Canyon and, after deposition, suffered a simi-
lar amount of deformation probably during the Grand Canyon orogeny. The
California strata apparently were deposited much closer to the shore line
than were those at Grand Canyon. Some search for fossils did not yield any
animal remains. Supposed algal structures are abundant in the limestones.
Deformation of the crust to form the basin in which the Grand Canyon and
southeastern California Algonkian deposits were laid down probably marks
the initiation of the southern part of the Cordilleran geosyncline as a great
basin of deposition.

Work on the report concerning the Grand Canyon Algonkian was contin-
ued during the year by my assistant, C. E. Van Gundy, and myself.

Researches on Paleozoic Stratigraphy in Grand Canyon, by Edwin D. McKee

Detailed stratigraphic studies of the Paleozoic formations in Grand
Canyon have been continued during the past year. Many important data
relating to the history of the Cambrian and Devonian rocks were obtained
during a boat trip down the Colorado River through the Grand Canyon.
This trip was made in the fall of 1937 under the leadership of Dr. Ian
Campbell. Important new information on the history of certain of the higher
formations has been obtained, largely through a series of trips by foot down
from the Canyon rims.

In the Cambrian rocks of Grand Canyon 35 collections of fossils, repre-
senting various horizons and localities between Grand Wash Cliffs to the
west and Marble Canyon to the east, have been made. These specimens
were examined by Dr. C. E. Resser, who states that a majority represent
undescribed species. He has recognized in the collections 12 genera of trilo-
bites, 8 of brachiopods, and 1 each of coral, cystid, gastropod, and sponge,
all of Lower and Middle Cambrian age.

By tracing individual members of the Cambrian formations westward
along the Colorado River, it has been possible to demonstrate certain strati-
graphic relationships heretofore open to question. The two most significant
of these are as follows:

1. The base of the massive limestone units (Muav) rises stratigraphically
toward the east by virtue of a lateral transition in type of sediment, present
in successively higher members from west to east.

2. The so-called "snuff dolomites," which have generally been considered

PALEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 359

good marker beds in the upper part of the Bright Angel shale, are at different
horizons in different localities and each is of relatively limited distribution.
They appear to represent lateral transition stages at various horizons between
massive limestones and green shales.

In the Devonian strata of western Grand Canyon it has been found prac-
tical to recognize in the formation five subdivisions based on lithologic and
physiographic character. These units can be recognized over a number of
miles, so should assist materially in determining detailed stratigraphic rela-
tionships across the entire area. The eastern margin of continuous Devonian
beds in Grand Canyon has been found to extend at least to the eastern side
of Great Thumb Point and probably to the vicinity of Garnet Canyon.

In the Supai formation statistical studies made of the angle and dip of
laminae in cross-bedded units have introduced a new complexity to the
problem. Some hundreds of readings made over a wide area have shown
little variation from a regional south-southeast dip among these laminse,
indicating a source somewhat west of north. This apparently conflicts with
conclusions as to the source of the sediment that have been drawn from the
increase of limestone beds westward and from the presence of relatively
coarser red beds, supposedly of the same age, east of Grand Canyon.

Geological Studies of the Archean Rocks at Grand Canyon, by Ian Campbell

and John H. Maxson

The season just passed saw the successful accomplishment of a major
event in Archean research in the Southwest; namely, the traverse of the
entire Grand Canyon section and mapping of all Archean exposures.

Previous field work on the Archean rocks of the Grand Canyon has been
carried out from fixed camps in the Bright Angel Quadrangle. The Vishnu
schist of Walcott,1 exposed in the Inner Gorge south of Vishnu Temple, was
described by him as consisting of micaceous schists and quartzites cut by
granitic dikes. Some subsequent investigators, not visiting any typically
meta-sedimentary section, concluded that the Vishnu schist was of igneous
origin. For many years the pre-Algonkian rocks of the Inner Gorge were
regarded as an insoluble igneous complex.

Recognizing the great significance of these old rocks in the elucidation of
the early history of the earth, Dr. John C. Merriam, President of the Carnegie
Institution, has personally encouraged field studies and research. In the
years from 1932 to 1937 detailed work in various parts of the Bright Angel
Quadrangle established the principal rock types and relationships. It is
pleasing to note that these give full substantiation to the pioneer observa-
tions of C. D. Walcott.

In summary, the Archean history of the Grand Canyon region embraces
four clearly distinguishable periods: (1) deposition of thick, monotonous
sedimentary formations, (2) volcanic eruption, (3) orogeny and granitic in-
trusion, and (4) subsequent erosion.

1. Sedimentation. A great thickness of sediments was laid down. These
were dominantly sandy clays but quartz sands and ferruginous beds were

1 C. D. Walcott. Pre-Cambrian igneous rocks of the Unkar terrane. U. S. Geol. Surv.
14th Ann. Rept., pt. 2, pp. 497-524 (1894).

360 CARNEGIE INSTITUTION OF WASHINGTON

also deposited. Some of the members were slightly calcareous but no lime-
stones were formed. Some characteristic sedimentary structures have sur-
vived despite subsequent metamorphism. Cross-bedding is common, well-
preserved ripple mark has been found, and ellipsoidal calcareous concre-
tions have been observed in what was originally an argillaceous sandstone.
It is believed that the sediments accumulated as marine deposits in a shal-
low, subsiding geosyncline.

2. Volcanism. Near the end of this period of sedimentation volcanism
occurred and basaltic lavas and tuffs were erupted. In some of the meta-
morphic derivatives "pillow structure" is still clearly discernible and prob-
ably indicates that these flows were submarine extrusions. A great thickness
of basaltic lava accumulated and sedimentation was interrupted, but at
intervals throughout this period small amounts of sandy clay were deposited.

3. Orogeny. Great northeast-southwest trending mountain ranges were
built. The sediments and lavas were folded and metamorphosed. The sandy
shales were converted into quartz-mica schists and the sandstones into
quartzites, while the basalts were changed to amphibolites. The more in-
tense stages of metamorphism, represented by such rocks as garnet-sillimanite
gneiss, were probably superimposed by contact-metamorphic processes dur-
ing the period of intrusion.

4. Intrusion. Perhaps concomitant with the declining phases of the orog-
eny, and very likely continuing after it, came intrusions of granitic magma.
These formed the larger bodies of the granite and gave rise to numberless
small dikes and to such phenomena as granitization of the meta-sediments,
production of migmatites, etc. The last event of the intrusive period is rep-
resented by the intrusion of abundant pegmatites, many of which form
lit-par-lit structures in the schists. The pegmatites together with the granite
are responsible for additional metamorphism of the meta-sediments and
lavas.

5. Ep-Archean erosion. During a very long period of erosion almost all
the relief of the land was obliterated.

In order to gain a coherent concept of the interrelationships, distribution,
and structure of the Archean rocks, it was recognized that an examination of
the entire exposed area was necessary. Accordingly a boat expedition down
the Colorado River from Lee's Ferry to Pierce's Ferry, Arizona, was under-
taken. Three especially constructed river boats were obtained and a com-
petent personnel was assembled. Mr. Frank B. Dodge, who had made
numerous trips on the Colorado, was employed as chief boatman and assisted
in the general organization. Through his skillful direction of the navigation,
mishaps were avoided and the journey was carried out successfully. Owen
R. Clark and Merrill F. Spencer, experienced boatmen, were likewise em-
ployed and contributed materially to the success of the expedition. In view
of the necessity of securing complete geological data on both sides of the
river during a rapid one-way traverse it was considered desirable to increase
the geological personnel. Therefore, Dr. J. T. Stark of Northwestern Uni-
versity, who had studied the Archean formations of the Rocky Moun-
tains, and Mr. Robert P. Sharp, who had formerly been a graduate assist-
ant at the California Institute, were invited to participate. Mr. E. D. McKee,

PALEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 361

Park Naturalist of Grand Canyon National Park, joined the expedition at
the foot of the Bass Trail to study Paleozoic stratigraphy during the re-
mainder of the trip. The writers greatly appreciated the cooperation and
enthusiasm shown by all members of the expedition, even under trying cir-
cumstances.

The program included mapping and collecting during slow descent of the
river. Transportation by boats proved highly successful and made accessible
large areas of Archean which had never been studied before. Observations
on structure and areal geology were made in tributary canyons of the Vishnu,
Bright Angel, Shinumo, and Havasu Quadrangles. The topographic "Plan
and profile of the Colorado River" prepared by the United States Geological
Survey party under Colonel Birdseye in 1923 furnished an accurate and re-
liable control for detailed work in the Granite Gorges. Supplementing this,
and of great value in locating structures and specimens in a precipitous ter-
rane, was a strip of overlapping vertical airplane photographs having a scale
of approximately 600 feet to the inch along the river. These covered all of
the Granite Gorges and some adjoining Paleozoic and Algonkian sections.

In perhaps few other places in the world can be found a section through
Archean terrane so continuously and so excellently exposed. For over 40
miles in the main Granite Gorge, for some tens of miles in the Middle
Granite Gorge, and for nearly 50 miles in the Lower Granite Gorge of the
Colorado, there is literally continuous outcrop of Archean rocks. Further-
more, because of the scour and polish of the swift, silt-laden waters of the
Colorado, outcrops at times exhibit surfaces comparable to those produced
by artificial laps, and textures and structures are displayed with surprising
clarity. Because of these features, much interesting detail on the intricate
processes of igneous invasion and of metamorphic recrystallization was ob-
tained. The porphyroblastic character of the majority of the gneisses in the
section is unmistakable ; and the replacement origin of much of the granite,
as well as of the gneiss, is strongly suggested.

The examination of the entire Archean section confirmed the earlier con-
clusion that the lithology of the meta-sediments is relatively uniform. No
new types were found. The great thickness of sediments varying only from
fine-grained, argillaceous sandstones (now quartzites and sericite-quartzites)
to sandy shales (now quartz-mica schists) is comparable to some sections of
the Belt series in the northern Rocky Mountain Province, where tens of
thousands of feet of fine-grained clastic sediments were deposited in late
pre-Cambrian time without change to limestone on the one hand or con-
glomerate on the other. As indicated later, there is some close folding in the
schist which renders any estimate of thickness only approximate. A mini-
mum figure is given by the steeply eastward-dipping section between Crystal
Creek and Monument Creek, which is approximately 5 miles across the
strike and only slightly injected by granite. Clearly exposed massive beds
preclude close folding and their non-repetition eliminates the possibility of
broad folding, either of which structures would exaggerate the thickness.
The schists east from Monument Creek to Bright Angel Creek should doubt-
less be added, but an estimate of their true thickness is impossible owing to
an increased amount of intrusion. Twenty-five thousand feet may therefore

362 CARNEGIE INSTITUTION OF WASHINGTON

be regarded as a minimum thickness for the meta-sediments, but their true
thickness may be twice as much.

For the meta-sedimentary rocks the authors propose the name Vishnu
series, a usage which will restrict the term "Vishnu schist," originally pro-
posed by Walcott for the entire Archean terrane. The name is appropriate
for two reasons: first, it perpetuates a term proposed by one of the leading
students of the pre-Cambrian of the past generation and one which is indelibly
associated with the Grand Canyon section; second, the section of Archean
rocks exposed in the lower canyon of Vishnu Creek is an excellent type lo-
cality, for all variations in character from relatively pure quartzites to
highly micaceous schists are present, as well as some of the rather unique
concretionary forms which seem to be distinctive of certain horizons of the
Vishnu series.

As a result of the river expedition amphibolite is recognized as a rock
type of formational importance. Some hundreds of feet were previously
known in the vicinity of Clear Creek, where amygdaloidal and ellipsoidal
structures were found preserved. Highly injected and granitized amphibo-
lites were known to occur between Cremation Creek and Horn Creek. The
expedition found in the Middle Granite Gorge and in isolated exposures in
Conquistador Aisle perhaps 4000 feet of amphibolite. Although most of
the outcrops show only massive amphibolite, there are some intercalations
of thin layers of quartzite and mica schist. The relationships are such as
to suggest that the amphibolites were in part basic flows and in part basic
tuffs. To this volcanic series a new formation name will be assigned.

The Vishnu series may be correlated with the Pinal schist of central
Arizona and with various Archean schists of the Great Basin. Its relation-
ship to the section of the Canadian Shield remains uncertain. There is no
compelling evidence of simultaneous Archean volcanic activity in widely
separated areas, yet the similarity of rock types and stratigraphic position
suggests correlation of the volcanic series with the Keewatin series of the
Lake Superior district.

Both the Vishnu series and the volcanics are older than any of the
plutonic rocks of the Grand Canyon. Indeed, no evidence was found indi-
cating more than one major period of igneous invasion, although there is evi-
dence that certain intrusives may belong to earlier, other to later stages
within the major cycle. In few places is there direct evidence of intrusion
on a batholithic scale. On the other hand, the suggestion is strong in many
places that the present section is cut chiefly along the roof and uppermost
portions of a large batholith, or batholiths, where small to moderate-sized
and irregularly shaped cupolas are abundantly exposed ; where recrystalliza-
tion, replacement, and pyrometasomatic effects in the adjoining and over-
lying country rocks have been of most intense degree; and where there has
been enormous development of pegmatite.

In contrast to the volcanic rocks, which are entirely of basic type, the
plutonic rocks are very largely acidic, ranging from tonalite to granite.
To what extent different exposures of somewhat different petrologic char-
acter should be separated, or to what extent they should be grouped as
cupolas belonging to a single parent batholith, is problematical.

PALEONTOLOGY, EARLY MAN, AND HISTORICAL GEOLOGY 363

In a broad way three principal intrusive groups may be recognized. The
first is the pink to red, microcline-rich, coarse-grained granite previously
described as the Zoroaster granite, which occurs in the Bright Angel Quad-
rangle. The largest single mass is a little over a mile across and lies in
and downstream from Zoroaster Canyon. The Zoroaster granite shows
similarity to the Algoman and other Archean granites of the Canadian
Shield. The second group is that described by L. F. Noble x as quartz diorite.
This outcrops over a large area in the Shinumo Quadrangle in the Upper
Granite Gorge. The third and largest mass is a coarse-grained gray granite
outcropping from the beginning of the Lower Granite Gorge to the Grand
Wash Cliffs.

Coincident with the emplacement of these plutonic bodies, there was a
vast amount of recrystallization (doubtless superposed upon a milder dy-
namic metamorphism) and metasomatism in the adjoining sediments and
volcanics. Metamorphic intensities varied considerably, even within short
distances, as evidenced by the presence of garnet-silliminite gneisses close
by fine-grained muscovite-biotite phyllites. In some cases there seems to
have been actual digestion or replacement of the country rock, and the
resulting blend of intrusive and meta-sediment is best considered as a mig-
matite. Rocks of this kind are well exposed in the vicinity of Phantom
Creek, and for this lithologic type (stratigraphically, of course, it represents
a mixture of schist and/or amphibolite with granite) we propose the name
"Phantom migmatite," thereby designating an accessible type locality and
at the same time recognizing the palimpsest and ghost-like features present
in this rock !

Pegmatites everywhere represent the last phase of plutonic activity. The
enormous development of these bodies is one of the outstanding, as well as
one of the most puzzling, features of the Archean in Grand Canyon. For
example, for some 25 miles west from Crystal Creek, across the general re-
gional strike, granite pegmatite accounts for from 10 to 50 per cent of the
section. Granite, on the other hand, accounts for considerably less of the
total section.

Evidence as to the origin of these pegmatites is still inconclusive. The
majority clearly fill primary joint cracks in the plutonic rocks, and as clearly
exhibit cross-cutting relationships in the schists, when viewed on a large
plan. Frequently, too, the spreading of schist folia under the force of igneous
intrusion is plain. Viewed in detail, however, conformity with schistosity is
often the rule, porphyroblastic development is common, and the evidence
for a replacement origin is often compelling. Furthermore, the volume rela-
tions are difficult to reconcile with a hypothesis of pure injection. The two
phenomena (injection and replacement) are of course by no means incom-
patible, and it may be that while igneous or aqueoigneous injection accounts
for the principal loci, much of the volume of these pegmatite bodies is due
to local but extensive replacement.

The paucity of distinctive mineralizers, as evidenced by the rarity of the
more unique pegmatite minerals, is worthy of comment. The great bulk of
the pegmatites consists of feldspar, quartz, muscovite, and little else. Black

XL. F. Noble, U. S. Geol. Surv. Bull. 549, pp. 35-36 (1914).

364 CARNEGIE INSTITUTION OF WASHINGTON

tourmaline is not uncommon, but is far from being abundant. Garnet is
somewhat more common. Beryl, in rare but often well-developed crystals,
is found in about half a dozen pegmatites in the entire section. Of other
minerals so frequently reported from pegmatites, no trace was found. Pos-
sibly this is further evidence favoring the idea of acrobatholithic structure,
in that the rarer and more volatile constituents might not deposit close to
the parent batholith. And if deposited farther away in the country rock,
they have been removed during ep-Archean erosion.

The orogeny following the deposition of the sediments and the extrusion
of the volcanics was of great magnitude and is probably to be correlated with
the Algoman revolution, now recognized as the most important in deforming
the Archean formations of the Canadian Shield. The stress was applied
in a southeast-northwest direction producing several broad folds of isoclinal
nature and numerous smaller folds. In some localities the small folds may
be recognized only by the intersection of flow cleavage with stratification,
elsewhere by relationships of drag folds and fracture cleavage on the fold
flanks. Excepting in the small folds, flow cleavage is parallel to the strati-
fication. The occurrence of bands of biotite oblique to the schistosity and
stratification was first noted by this expedition on Vishnu Creek and was
interpreted as representing fracture cleavage. Subsequently this feature was
found to check in attitude with that required for development in conjunc-
tion with drag folds on fold flanks. In Walthenberg Canyon similar frac-
ture cleavage bands were found cutting across a small fold wherein the flow
cleavage was parallel to the fold surfaces, thereby recording two periods
of deformation somewhat separated in time. The granitic rocks are believed
to have been intruded late in the epoch of orogeny. Much of their foliation
is a relict of the assimilated schists.

Archean faulting was recognized at several localities by offset pegmatite
dikes where the fault plane was later intruded. Many faults in the Archean
were mapped and in some instances it was possible to demonstrate that the
movement occurred in pre-Algonkian time. Throughout the Grand Canyon
evidence was obtained that later and often recurrent faulting has been de-
pendent on Archean and Algonkian blocks.

The Carnegie Institution Grand Canyon Expedition was very successful
in gaining new information on the Archean geology of northern Arizona and
in clarifying points previously in doubt. There remain, however, certain
unsolved problems on which future work should throw light. For example :
no basement, on which the Archean sediments were deposited, has as yet
been found. Correlation with other pre-Cambrian occurrences throughout
the Southwest is not yet definite ; but the subdivision of the Grand Canyon
section into distinct formations by this expedition is an important first step
in making such correlations possible. A reconstruction of Archean palseo-
geography would not only be of local significance, but would have broader
geophysical and historical importance. The relationships between the
Archean batholiths of the Grand Canyon and those of the Basin Ranges are
not yet fully understood. For the immediate future it is hoped that by ex-
tending field work in the vicinity of Lake Mead some contribution to these
problems may be made.

PHYSICS

Committee on Coordination of Cosmic-Ray Investigations. Progress
report for the period July 1937 to June 1938. (For previous reports
see Year Books Nos. 32-36.)

Instruments. The Institution's precision cosmic-ray meters were con-
tinued at the following stations: Cheltenham Magnetic Observatory of the
United States Coast and Geodetic Survey, meter C-l, George Hartnell in
charge; Huancayo (Peru) Magnetic Observatory of the Institution's De-
partment of Terrestrial Magnetism, meter C-2, F. T. Davies in charge;
National Astronomical Observatory of Mexico at Teoloyucan, D. F., meter
C-4, Dr. Joaquin Gallo in charge ; Amberley Branch of the Christchurch
(New Zealand) Magnetic Observatory of the Department of Scientific and
Industrial Research of New Zealand, meter C-5, J. W. Beagley in charge.

The installation of meter C-6, to complete the network of five stations
as originally planned by the Committee, was made at Godhavn, Greenland.
Before shipment the meter was improved by Dr. Compton and his assistants
to permit exposure to cold weather without damage as shown by outdoor
tests to 0° C and in the laboratory to considerably lower temperatures. De-
tailed arrangements on behalf of the Committee were made by Dr. Fleming
with Dr. la Cour for the installation. Dr. la Cour designed the special-type
building suited to the climate at Godhavn. This design was completed in
May and building materials and the cosmic-ray meter, with 1200 kg of
3-mm lead shot purchased in Norway, were shipped from Copenhagen June
4, the meter having been forwarded directly from Chicago to Copenhagen
in May. Batteries and recording paper sufficient for a year's operation were
furnished because supplies may be forwarded only in the summer. Ex-
penses of shipment, building, and shot were paid by the Committee. The
Danish government, besides providing transportation to Greenland, and
travel and living expenses of Mr. V. Laursen of Dr. la Cour's staff for five
months, generously made a credit of 11,000 Kr. (about $2500) for ex-
penses including insurance, assistants, heat, and supplies at the Observatory.
On October 12, 1938, a cablegram from Dr. la Cour stated the meter was
then in operation. The addition of this station, which completes the net-
work proposed by the Committee, will furnish additional data for study and
interpretation, valuable particularly as Godhavn is in such high latitude
(69° 15' north) and is relatively quite close to the geomagnetic pole.

Dr. R. D. Bennett at Massachusetts Institute of Technology continued
experimentation and improvement of meter C-3. Plans were made for its
installation late in 1938, in connection with high-altitude studies, at Climax,
Colorado (12,000 feet above sea-level) ; this point on Mount Evans was
selected instead of the summit (14,000 feet) because it is accessible through-
out the year. This station will be under the supervision of Dr. J. C. Stearns
of the University of Denver. Dr. Bennett at the Massachusetts Institute of
Technology, Dr. Jesse at the University of Chicago, and Mr. Forbush at
the Department of Terrestrial Magnetism have made improvements to re-
duce considerably the current required for operation. This will reduce the
cost of replacements of batteries. Heretofore the National Carbon Com-

365

366 CARNEGIE INSTITUTION OF WASHINGTON

pany has generously contributed batteries — a contribution the Committee
wishes again to acknowledge gratefully.

Meter C-0 under the direction of Dr. Compton continued in use on
cruises in the Southern Pacific Ocean during the year. During the next
year he plans to operate this meter on vessels cruising between Seattle,
Washington, and Alaska.

The Institution's three Millikan-Neher cosmic-ray meters were continued
in operation at the Kensington (Maryland) station of the Department of
Terrestrial Magnetism for comparison with the precision-meter records at
Cheltenham, for studies of the comparative behavior of the two types of in-
struments, and for determination of barometic and thermal coefficients.

Because of unsatisfactory performance of batteries of European manu-
facture the records with Steinke cosmic-ray apparatus at the University
of Cape Town were defective. However, P. Gaskell, in charge under the
supervision of Professor R. M. James of the Department of Physics of the
University of Cape Town, succeeded in making from several unserviceable
sets of batteries live sets so that good records were again obtained from
June 17, 1938. New batteries were ordered from Europe.

Instrumental technique for determination of the cosmic radiation in the
upper atmosphere was further developed by Drs. Millikan, Johnson, and
Korff, as indicated in their reports which follow.

Investigations. Forbush's work last year on the relationship between
disturbances of the cosmic radiation and of the Earth's magnetism stimu-
lated wide interest; evidence of this appears in coordination of effort indi-
cated by reports of Messrs. Beagley, Forbush, Johnson, and Korff, which
follow. The large variation in magnitude of cosmic-ray effects during dif-
ferent magnetic storms indicates that the current-system responsible for
different storms flows at different heights about the Earth.

From July 1 to December 31, 1937, Mr. Forbush of the Department of
Terrestrial Magnetism devoted about half of his time to cosmic-ray investi-
gations. Beginning with January 1, 1938, on furlough from the Depart-
ment, he was paid by the Committee and gave full time to the reduction,
discussion, and interpretation of cosmic-ray records obtained at the Com-
mittee's four stations with the assistance of W. R. Maltby (from December
20, 1937). He completed the discussion begun by Korff of the comparison
of the Millikan-Neher and Compton-Bennett meters. He also determined
their barometric and thermal coefficients. He discussed statistically solar,
sidereal, and annual variations, and bursts of cosmic radiation. An out-
standing result during the year based on the records obtained at Chelten-
ham, Teoloyucan, Huancayo, and Christchurch is Mr. Forbush's discovery
of positive evidence of worldwide changes in cosmic-ray intensity which are
quite similar at all stations, as indicated in his report below.

In the study of cosmic-ray intensity at high elevations Dr. Johnson spent
some time in Minnesota and Canada. At Swarthmore in collaboration with
Dr. Korff he further developed single-counter measurements of cosmic-ray
observations at high elevations. The technique was greatly enhanced by
the development of a radio barograph suitable for balloon flights. As indi-

physics 367

cated in Dr. Johnson's report, he has further improved the coincident-
counter recording of cosmic-ray intensity. The further analysis of geomag-
netic cosmic-ray effects shows the field of cosmic-ray measurements at sea-
level to be produced by primary radiations, approximately 100 per cent
positive.

In Dr. Korff's report is to be noted particularly the cooperation with
the National Bureau of Standards and the resulting improvement effected
in instrumental appurtenances for high-altitude observations. He has
given further attention to the study of the longitude-effect from the counter
observations made on flights in Peru and found it to be about 25 per cent
at the point of maximum cosmic-ray intensity in the stratosphere as com-
pared with about 4 per cent at sea-level as found by Dr. Millikan.

Dr. Millikan and his associates at the California Institute of Technology
made substantial contributions in cosmic-ray investigations including studies
(1) on the total cosmic-ray energy entering the atmosphere at different
latitudes, (2) on the discovery by cloud-chamber technique of penetrating
charged particles of intermediate mass between electrons and protons, and
(3) on development of a Geiger counter of high resolution for cosmic-ray
meter.

Future program. Funds provided by the Carnegie Corporation for the
work of the Committee in 1938, as approved by President Merriam, included
(1) continuation of program with precision cosmic-ray meters at five sta-
tions and of Steinke meter at Cape Town; (2) continuation of high-altitude
research to include observations on mountains and by balloons; (3) develop-
ment of cosmic-ray counter technique; (4) full-time services of S. E. For-
bush and W. R. Maltby for interpretative studies of accumulated records
between precision meters; and (5) full- and part-time services of assistants
for work being done under Dr. Millikan's direction at the California Insti-
tute of Technology.

Several memoranda on possible interrelations of cosmic-ray intensity and
geomagnetic variations were prepared by personnel of the Department of
Terrestrial Magnetism. Members of the Committee had frequent contact
and conferences with Drs. R. D. 3ennett, A. H. Compton, T. H. Johnson,
S. A. Korff, and R. A. Millikan, research associates of the Institution, and
other investigators mentioned above and in the reports which follow. These
and previous reports evidence good progress towards resolution of the
complexities of cosmic radiation.

W. S. Adams
J. A. Fleming
F. E. Wright

Beagley, J. W., Christchurch Magnetic Observatory, Christchurch, New
Zealand. Cosmic-ray investigations.

Maintenance. Cosmic-ray meter C-5 was operated throughout the past
report year with only minor interruptions. These were due chiefly to the
necessity of adding argon to the bomb to maintain the pressure approxi-
mately constant.

368 CARNEGIE INSTITUTION OF WASHINGTON

Reduction of data. Hourly scalings of all cosmic-ray records were kept
current. These include departures from balance, bursts, barometric pres-
sure, and temperatures both outside and inside the observing room.

Cosmic radiation and magnetic variations. Following the discovery by
Forbush of changes in the intensity of cosmic radiation occurring simul-
taneously with changes in magnetic horizontal intensity during the mag-
netic storm of April 24, 1937, the records during succeeding magnetic
storms were closely examined for confirmation of this magnetic-storm effect.

This was forthcoming during the intense magnetic disturbance which oc-
curred during January 17-26, 1938, when simultaneous decreases of cosmic-
ray intensity were recorded. These decreases varied from 3.7 per cent to
5.4 per cent at different periods of the storm.

A preliminary investigation to determine whether such an effect is asso-
ciated with minor magnetic disturbances was made. In the particular
storms selected the decreases of cosmic-ray intensity were small and of the
same order as the variability in the daily means, so too much weight can-
not be attached to them. As the disturbances were only of short duration
and the decreases in magnetic horizontal intensity were not very great, it is
probable that the magnetic moments of the storm-current systems may
have been too small to alter the cosmic-ray intensity appreciably.

Seasonal effect. Preliminary investigation of one year's results from the
cosmic-ray meter at Christchurch seems to indicate a seasonal variation.
Its amplitude is approximately 1 per cent of the total intensity, with a maxi-
mum in winter (July).

Azimuthal asymmetry observations. D. M. Hall, of the Observatory's
staff, conducted observations on the asymmetry of the cosmic radiation at
Christchurch. For this purpose a set of Geiger counters with circuit after
Barasch was used. The following conclusions were drawn:

1. An asymmetry in cosmic radiation extends as far south as geomagnetic
latitude 48°.

2. The asymmetry is at a maximum at an angle of 30° from the zenith.

3. The magnitude of the asymmetry at this angle is approximately 2 per
cent and is of the same order as that obtained in the corresponding latitude
in the Northern Hemisphere.

4. The latitude-effect should extend farther south than Christchurch.

5. Positive primary rays are not wholly responsible for the asymmetry.

Mr. Hall intends to extend his observations further in this field and is
also endeavoring to arrange his apparatus to obtain continuous records of
the vertical cosmic-ray intensity.

Forbush, S. E., Department of Terrestrial Magnetism, Washington, Dis^
trict of Columbia. Statistical investigations of cosmic-ray variations.
(For previous report see Year Book No. 36.)

Reduction of data. All scalings, with adequate checks, of records ob-
tained with Compton-Bennett meters from Cheltenham (C-l) and Huan-
cayo (C-2) were kept current. This includes scalings of departures from
balance, of bursts, and of barometric pressure. In addition, several months'

physics 369

records from two Millikan-Neher electroscopes at Kensington, Maryland,
which had been maintained at constant temperature from March to May
1938, were carefully scaled to provide information concerning the tempera-
ture-coefficient of meter C-l at Cheltenham. Daily means of cosmic-ray
intensity, corrected for barometric pressure, were kept current for Chel-
tenham and Huancayo.

The daily mean values of cosmic-ray intensity from April 1936 to De-
cember 1937 at Christchurch, New Zealand, were reduced to constant baro-
metric pressure. This reduction was considerably hampered by escape of
argon from the bomb of meter C-5.

Reduction of several weeks of cosmic-ray records, which were obtained
at Massachusetts Institute of Technology and loaned to us by Professor
R. D. Bennett, proved particularly useful in the study of magnetic-storm
effects.

The investigation of the magnetic-storm effect on cosmic-ray intensity
involved the scaling and checking of some 60 days of magnetograms at the
United States Coast and Geodetic Survey.

Inter comparison of instruments. Because of its important bearing upon
the temperature-coefficient of Compton-Bennett meter C-l at Cheltenham,
a thorough study was made of a preliminary report by Dr. Korff upon the
results of the intercomparisons of Millikan-Neher and Compton-Bennett
meters. It was found that the technique used in scaling the Millikan-Neher
records was not sufficiently reliable to insure satisfactory data. Using a
newly-purchased Argus projector for 35-mm film, a reliable technique was
devised for scaling the Millikan-Neher records.

Daily means of cosmic-ray intensity from Compton-Bennett meter C-l
at Cheltenham were compared with daily means for 51 and 132 days, re-
spectively, from Millikan-Neher meters 0 and 1. Over each of these inter-
vals the maximum change in cosmic-ray intensity was about 6 per cent,
owing to barometric and other causes. Statistical analyses showed that the
relation between the percentage-changes in daily means, over the respective
periods, given by the two types of instruments was 1.00 ±0.04. In addition,
it was found that the variance (square of standard deviation) in the mea-
sured daily means for the Millikan-Neher meters was about four times that
for the Compton-Bennett meter. This result will be useful in determining
the relative merits of the two types of instruments for special investigations.
Temperature-coefficient of Compton-Bennett meter C-l at Cheltenham,
Maryland. Daily means from two Millikan-Neher electroscopes at con-
stant temperature were compared with those obtained from Compton-Ben-
nett meter C-l at Cheltenham when the temperature of the latter was varied
about 15° C. Statistical analysis showed that the differences between the
daily means obtained from the two types of meters did not depend upon the
temperature of the Compton-Bennett meter C-l. Thus it is quite certain
that meter C-l at Cheltenham has a negligible temperature-coefficient. It
is now also certain that the large annual variation (range 3 per cent) in
cosmic-ray intensity at Cheltenham cannot be ascribed to an annual varia-
tion in the temperature of the meter.

370 CARNEGIE INSTITUTION OF WASHINGTON

Following this phase of the investigation the temperature of the Millikan-
Neher meters at Kensington was varied over a range of about 10° C.
Analysis showed that the results from Millikan-Neher meter 1 were also
not affected by temperature. Owing to mechanical difficulties which de-
veloped in the charging mechanism inside the ionization-chamber of Milli-
kan-Neher meter 0, it was not possible to determine whether that instru-
ment was affected by temperature.

Results from Milliken-Neher meter 1 at Kensington were compared with
those from Compton-Bennett meter C-l at Cheltenham for several periods
of a month or more at intervals with a maximum separation of 16 months.
The results showed that the differences between the two instruments re-
mained constant within about 0.2 per cent of the total cosmic-ray intensity.
This makes it certain that the annual variation in cosmic-ray intensity indi-
cated by meter C-l at Cheltenham would also be indicated by Millikan-
Neher meter 1 at Kensington.

Barometric coefficients. Statistical analyses were made to determine the
barometric coefficient and its reliability, separately, from daily means for
each of the 22 months' data available for Christchurch. The results proved
useful in checking the reduction of the observed values of cosmic-ray in-
tensity to constant pressure of argon. The coefficient for Christchurch was
found to be significantly different from that which had been obtained at
Cheltenham for meter C-l when used with bomb 3.

Thus it was necessary to redetermine the barometric coefficient from the
results at Cheltenham following the replacement, in March 1937, of bomb
3 by bomb 1 in meter C-l. Statistical analyses were accordingly made to
determine the coefficient and its reliability for each of 15 months' data at
Cheltenham. These results were in excellent accord with those obtained
from Christchurch, for which the altitude and geomagnetic latitude are
practically the same as for Cheltenham. Thus an important check was
furnished on the effective sensitivity of the two meters, which is essential
to an adequate comparison of changes in intensity due to other causes. The
cause for the discrepancy between the coefficients obtained at Cheltenham
from meter C-l using bombs 3 and 1 is probably connected with the fact
that the first of these bombs had a definitely anomalous saturation-char-
acteristic and also an anomalous temperature-coefficient.

Solar diurnal variation. Analysis has been made of the solar diurnal
variation of cosmic-ray intensity at Huancayo, Peru, from data covering
some 15 months. The solar diurnal variation at Huancayo agrees approxi-
mately in phase and amplitude with that found for Cheltenham, Maryland.
These results should provide an important test of the theory, advanced by
M. S. Vallarta, that the solar diurnal variation is due to the Sun's mag-
netic moment. Some progress was made in statistical tests of other possible
causes for the solar diurnal variation.

Sidereal diurnal variation. An analysis of data for 595 days at Chelten-
ham indicated that the apparent 24-hour sidereal wave in cosmic-ray inten-
sity at this station cannot be regarded as statistically significant. Analysis
of data for 396 days from Huancayo, Peru, indicates an apparent sidereal
wave, the statistical significance of which has not been tested, which is not

PHYSICS 371

in agreement with that for Cheltenham or with that predicted from the
theory of Compton and Getting.

Bursts. A preliminary investigation was made of the dependence of the
frequency of bursts upon size, based on data for 500 days each at Chelten-
ham and at Huancayo. It is found that bursts of a given size occur from
2.5 to 3.2 times more frequently at Huancayo than at Cheltenham. The
decrease of burst- frequency with size is nearly the same for both stations.

Annual variation. Having eliminated the possibility that the large
annual variation of cosmic-ray intensity (range about 3 per cent) at Chel-
tenham, Maryland, might be due to an annual variation of instrument-
temperature, progress is being made toward a comparison of the annual
variation there with that from Huancayo, Peru, and that from Christ-
church, New Zealand. The results obtained from the analysis of the annual
variation will provide further check upon the theory that this may be
caused by the magnetic moment of the Sun.

Magnetic-storm effects on cosmic-ray intensity. Most important to
theories of magnetic storms are the results of observations on the effects on
cosmic-ray intensity associated with magnetic storms. It is now definitely
established that worldwide changes of several per cent in cosmic-ray in-
tensity, which were first discovered at the Department of Terrestrial Mag-
netism, occur during some magnetic storms. Equally definite is the evidence
that magnetic storms of equal intensity at the Earth's surface occur without
appreciable effects on cosmic-ray intensity. It is found that the ratio of
changes in cosmic-ray intensity to those in horizontal magnetic intensity is
quite constant during an individual magnetic storm. This is an indication
that one and the same current-system is responsible for the changes in hori-
zontal magnetic intensity and those in cosmic-ray intensity. The large
variation in the magnitude of cosmic-ray effects during different magnetic
storms indicates that the current-system responsible for the different storms
flows at different heights above the Earth. It appears improbable that
the current-systems of storms with and without cosmic-ray effects both
flow within the Earth's atmosphere.

Assuming the current-system for the storm-time field for the two types of
storms to consist of a ring concentric with the Earth in the geomagnetic
equatorial plane, magnetic data from several observatories were analyzed
to determine whether the radius of the assumed ring is, as would be ex-
pected, greater for magnetic storms which affect cosmic-ray intensity.

Although the analysis is not conclusive on this point, the results satisfy
a necessary condition for the existence of such a ring-current. The occur-
rence of aurora in temperate latitudes during most of the magnetic storms
which affected cosmic-ray intensity is interpreted, after Stormer, to indi-
cate the existence of such ring-currents. The percentage-changes in cosmic-
ray intensity during magnetic storms is, within the observational uncer-
tainty, the same at geomagnetic latitudes 50? 1 north and 0?6 south. The
significant correlation between changes in daily means of cosmic-ray in-
tensity for two stations separated 50° in latitude probably results from
the same mechanism responsible for the magnetic-storm effects.

372 CARNEGIE INSTITUTION OF WASHINGTON

On worldwide changes in cosmic-ray intensity. Based on cosmic-ray re-
sults from Cheltenham, Teoloyucan, Huancayo, and Christchurch, it is
found that the data indicate that:

1. At Huancayo there is no 12-month wave of appreciable amplitude.

2. At Cheltenham there is a 12-month wave, maximum in January, with
amplitude about 1.6 per cent of the total cosmic-ray intensity.

3. At Teoloyucan there is a 12-month wave, maximum in January, with
amplitude about 1.0 per cent of the total cosmic-ray intensity.

4. At Christchurch there is a 12-month wave, maximum in July, with
amplitude about 0.8 per cent of the total intensity.

5. There is a high correlation between the monthly means at any two
stations after removing the 12-month waves.

6. There is a high correlation between the means for each one-third of a
month at any two stations after removing the 12-month waves.

The indications (5) and (6) give positive evidence of worldwide changes
in cosmic-ray intensity which are quite similar at all stations. In addition
to these worldwide changes, there exist 12-month waves in the data which
have opposite phases in the two hemispheres. It seems impossible to in-
terpret the 12-month waves in such a way as could be explained by the
hypothesis of a solar magnetic field proposed by M. S. Vallarta, since he
concludes that this should give rise to an annual variation with maximum
in northern summer.

Statistical analyses of the worldwide changes give consistent evidence
that, when expressed in percentage of the absolute cosmic-ray intensity at
each station:

1. The worldwide changes at Cheltenham and Christchurch are each be-
tween about 5 and 10 per cent greater than at Huancayo.

2. The worldwide changes at Teoloyucan are approximately 50 per cent
greater than at Huancayo or at Cheltenham.

The difference in altitude between Huancayo and Christchurch and be-
tween Huancayo and Cheltenham introduces uncertainty concerning a pos-
sible latitude-effect at sea-level in the worldwide changes in cosmic-ray
intensity. If the absolute values of cosmic-ray intensity at Teoloyucan and
Huancayo are accepted, then, since the elevations of these two stations are
not greatly different, the fact that the worldwide changes at Teoloyucan are
about 50 per cent greater than for Huancayo would have to be ascribed to
difference in latitude. Also the difference between Teoloyucan and Chelten-
ham would have to be ascribed to difference in elevation. Results from a
high-altitude station such as Mount Evans not only would be useful con-
cerning this point, but would indicate also whether the amplitude of the
12-month wave depended upon elevation.

In any case the present investigation shows that the worldwide effect in
cosmic-ray intensity can be compared at different stations with a reliability
which is probably at least as great as the reliability with which the absolute
values of cosmic-ray intensity at different stations are known.

Finally, it should be pointed out that the effects here discussed could not
have been found unless all the meters involved had remained remarkably

physics 373

stable. Thus the worldwide effects in cosmic-ray intensity provided in-
directly a test upon the stability of instruments at the different stations.

While worldwide effects in cosmic-ray intensity were previously known
to exist during some magnetic storms, it was not anticipated that there
were changes in cosmic-ray intensity over long periods which, as shown
in this investigation, are also worldwide in character. That these world-
wide changes appear roughly to decrease with increasing magnetic activity
suggests that the mechanism responsible for them is similar to that for the
magnetic-storm effect.

Messrs. George Hartnell, J. W. Beagley, and F. T. Davies of the Chelten-
ham, Christchurch, and Huancayo observatories, respectively, have had
charge of the meters, the records from which have supplied the data for the
above discussions. From July to December 1937 the writer, as one of the
staff of the Department of Terrestrial Magnetism, gave part-time service
to the reductions; from January 1938, while on temporary furlough from the
Department of Terrestrial Magnetism, he devoted full-time service to
this work. Since December 20, 1937, he has been fortunate in having the
assistance of W. R. Maltby.

Johnson, Thomas H., Bartol Research Foundation, Swarthmore, Pennsyl-
vania. Studies of cosmic rays. (For previous reports see Year Books
Nos. 32-36.)

The cosmic-ray intensity at high elevations in northern latitudes. The
radio balloon technique developed with support of the Carnegie Institution
during the previous year has been used for studies of the low-energy end
of the cosmic-ray spectrum. Flights were made in Swarthmore, Pennsyl-
vania, where the minimum energy for vertically entrant cosmic rays is 3.5
bv (billion volts), in northern Minnesota where the minimum energy is
2 bv, and in Churchill, Manitoba, where the minimum energy is 1 bv. Any
differences in the intensities at these stations can be attributed to the cosmic
radiation in the energy-interval between the respective low-energy limits.
Satisfactory data were obtained at the two northern stations for all depths
in the atmosphere greater than 2 meters of equivalent water and for some-
what lesser depths at Swarthmore. Within the experimental uncertainties,
estimated as of the order of 5 per cent, the intensities were the same at all
three stations. This finding is also in agreement with the results of Car-
michael and Dymond, and of Bowen, Millikan, and Neher, whose experi-
ments have been reported since the conclusion of these studies.

An analysis of all the high-elevation experiments in northern latitudes
shows that it is not possible to conclude that there are fewer cosmic rays in
the low-energy region of the spectrum than in the higher-energy regions.
Because of the low energy contributed by each ray there could be a larger
number of rays in this region without there being any detectable contribution
to the measured intensity even at the highest attainable elevations. The
multiplication of secondaries plays such an important role in the first layers
of the atmosphere that the intensity which one measures is more closely
proportional to the incident energy than to the number of primary rays. The

374 CARNEGIE INSTITUTION OF WASHINGTON

results are consistent with a distribution in which the number of rays can
be represented by an exponential function of the energy.

Single counter measurements of the cosmic radiation at high elevations.
In collaboration with Dr. S. A. KorfT, radio balloon flights have been made
in Swarthmore in which single counters have been used for the measurement
of the cosmic-ray intensity. In this work we have attempted to achieve
the same statistical accuracy as has been realized in the electroscope-meas-
urements of Bowen, Millikan, and Neher. Large-sized counters, discharging
several thousand times a minute, have been used in conjunction with a
simple scaling circuit to reduce the actual count by an adjustable factor
for convenience in transmitting and recording the signals. A measurement
of the intensity accurate to about 1 per cent can be made in one minute
with this technique. One of these flights was adjusted to level off at the
ceiling, which happened to be 66,000 feet, and the instrument continued
to record and transmit the intensity at this elevation for a period of eight
hours. Another of these flights went to 80,000 feet.

Although these investigations have not been carried far enough to yield
publishable results, some preliminary data have been obtained which bear
upon the following problems: (a) the diurnal variation of the cosmic-ray
intensity at the top of the atmosphere and possible solar contributions to the
soft component of the cosmic radiation; (6) the effect of magnetic storms
upon the cosmic radiation at the top of the atmosphere; and (c) the possible
existence of X-rays or gamma-rays in the high atmosphere emanating from
the Sun during solar eruptions, and an attempt to find by Geiger counter
technique the radiations which produce the radio fade-outs.

Development of a radio barograph suitable for cosmic-ray studies. An
aneroid barograph free from hysterisis and back-lash has been devised
which uses the Olland-Curtiss principle. A nonlinear scale gives greater
sensitivity at low pressures and the instrument is accurate to within about
1 mm at the low-pressure end and to within about 3 mm at the high-pressure
end.

Development of technique for projected coincidence counter studies of the
directional distribution of the cosmic radiation at high elevations. A tech-
nique for the control of the orientation of the balloon apparatus has been
developed. With our leveling-off technique we are now in a position to
carry on the measurements of the directional distribution of cosmic rays
at high elevations. This work is projected for the near future.

Continuous coincidence counter recording of the cosmic-ray intensity. The
apparatus used in previous years for automatic shipboard recording of the
cosmic-ray intensity has been operated for most of the past year in Swarth-
more. The large fluctuations found in high latitudes during the shipboard
recordings have been confirmed and an attempt has been made to correlate
these with the absolute humidity. Two sets of data comprising 70 days and
51 days respectively have been subjected to a least squares analysis in which
barometric and humidity coefficients were evaluated simultaneously. Large
humidity coefficients were found in the sense that high humidity correlates
with a low cosmic-ray intensity, but the correlation is not a close one as in
the case of the barometer-effect.

physics 375

Further analysis of the geomagnetic cosmic-ray effects. The positive-
negative composition of the primary cosmic radiation has been determined
by a new type of analysis from the asymmetry measurements of the 1933-
1934 surveys and from Compton and Turner's recent measurements of the
sea-level latitude-effect. The measurements of Compton, of Hoerlin, and of
the writer on the variation with elevation of the geomagnetic effects have
been used in converting the electroscope data of the latitude-effect to corre-
spond to the intensities of vertically entrant radiation. The result of the
new analysis shows, with a greater accuracy than was realized in former
attempts, that the field sensitive cosmic rays at sea-level are produced by
a primary radiation which is practically 100 per cent positive. The experi-
mental accuracy will not permit a negative component exceeding 10 per cent
of the total field sensitive radiation. Experiments of the 1934 survey, as
well as similar experiments by Korff and Rossi in which lead shields were
used during the measurement of the asymmetry, can now be interpreted in
the light of our present knowledge of the hard and soft components of the
cosmic radiation, as indicating that the asymmetry is a property of the
penetrating component. The soft component which constitutes a large part
of the cosmic radiation at high elevations may be equally positive and
negative.

Our present knowledge of the primary cosmic radiation may be sum-
marized as follows: (1) The hard component primaries are entirely positive
(asymmetry and latitude-effect analyzed by Lemaitre and Vallarta theory).
(2) The soft component primaries are electronic (intensity-depth curve at
high elevations consistent with the theory of electron multiplication), and
these rays are probably equally positive and negative (necessity of a neutral
condition in intergalactic space and evidence for complete symmetry of
shower-particles on mountain tops). (3) The gamma radiation is far too
faint in comparison with the electron component to represent an equilibrium
between cosmic rays and matter (latitude-effect of cosmic rays at high ele-
vations). (4) The positive hard component primaries must be accompanied
in intergalactic space by negatives of equal velocities and of equal space
density (to preserve a neutral intergalactic space). The absence of these
negatives in the sea-level radiation can be easily accounted for by supposing
that the negatives are electrons while the positives are protons. The heavier
positives will carry most of the energy (since the velocities are equal) and
will pass readily through the Earth's field, whereas the negatives will be
deflected. Within the atmosphere these primary protons produce the sec-
ondary penetrating component, consisting of heavy electrons and possibly
neutrettos.

Personnel. The experiments in Minnesota and Manitoba were made with
the help of John Marshall, Jr. A. A. McKenzie helped with the prep-
aration of the instruments. The Minnesota Department of Conservation
through the courtesy of G. M. Conzet supplied facilities and additional
personnel for the Minnesota experiments, and J. Patterson of the Canadian
Meteorological Service arranged for the Churchill experiments. Dr. S. A.
Korff and Roy W. Prince have cooperated in the recent work in Swarth-
more. Miss Carol Lipman has helped with the reduction of data.

376 CARNEGIE INSTITUTION OF WASHINGTON

Korff, S. A., Department of Terrestrial Magnetism, Washington, District
of Columbia, and Bartol Research Foundation, Swarthmore, Penn-
sylvania. Cosmic-ray investigations. (For previous report see Year
Book No. 36.)

The investigations made during the year 1937-1938, with the aid of funds
allotted by the Carnegie Corporation through the Carnegie Institution of
Washington, may be divided into two parts: (a) a long-range program for
the comparison of identical and different meters over long periods; (6) the
study of cosmic radiation at high elevations, the data being automatically
transmitted from free balloons by short-wave radio.

Program of meter-comparison. Records obtained at the Huancayo Mag-
netic Observatory, at a station occupied at Ticlio, Peru (elevation above
sea-level 15,600 feet) , and at the Kensington, Maryland, laboratory of the
Department of Terrestrial Magnetism have been measured and bursts in the
intensity of cosmic radiation have been classified and compared. The
bursts were studied to ascertain whether there was any variation of fre-
quency of occurrence, or of energy-distribution, with latitude. The primary
cosmic rays are more energetic, on the average, in the equatorial zone,
where rays below 15 X 109 electron-volts are excluded by the Earth's mag-
netic field, and hence some latitude-effect in the bursts might have been
anticipated. The bursts were found to have the same distribution-in-energy
at all stations. The frequency of occurrence of bursts at Huancayo is not
essentially different from that found by other observers at similar eleva-
tions in northern latitudes. The bursts were found to increase with eleva-
tion at a rate much faster than the total radiation. This is in accord with
the view that bursts and showers constitute one of the chief mechanisms
through which cosmic rays lose energy as they pass through the atmos-
phere. The observations further indicate that the bursts are produced by
the "soft" component of the radiation, of which only a small fraction
reaches sea-level.

The operation of the three Millikan-Neher meters of the Carnegie Insti-
tution of Washington at the Kensington Radio Laboratory of the Depart-
ment of Terrestrial Magnetism was continued during most of the past re-
port-year by Forbush. Records are now available for about one year from
each instrument. Maintaining two of the Millikan-Neher instruments at
constant temperature for about three months, while the temperature of the
Compton-Bennett meter C-l at Cheltenham was varied, enabled Forbush
to show that the temperature-coefficient of meter C-l is, within the small
statistical uncertainty, zero. Similarly, no effect of temperature on Milli-
kan-Neher meter 1 was found. Results from Millikan-Neher meter 1 and
from Compton-Bennett meter C-l for three periods of several weeks, sep-
arated by as much as one year, have been analyzed by Forbush and indicate
excellent agreement between the two instruments.

Radio-transmitted balloon observations. Two programs have been car-
ried out, continuing the observations of cosmic-ray intensities in the strato-
sphere and the transmission of the data by radio from free balloons.

physics 377

Flights in cooperation with the National Bureau of Standards. The proj-
ect of cooperation with the National Bureau of Standards was carried to
completion, and a series of flights was made at Washington. In some of
these flights, altitudes of over 100,000 feet were attained. The cosmic-ray
intensities observed in these flights indicated (a) that a satisfactory agree-
ment may be obtained between counter- and electroscope-measurements in
the stratosphere and (6) that the intensity at high elevations is consid-
erably lower than it is at about 60,000 feet. This latter effect further serves
to emphasize the conclusion previously drawn that the bulk of ionization
measured in the upper atmosphere is produced by secondaries. The rapid
increase in the production of secondaries as the primaries penetrate the
first 5 per cent of the Earth's atmosphere gives support to the Carlson-
Oppenheimer theory of energy-loss through the production of multiplicative
showers.

A flight was also made at Balboa, Canal Zone — the first to be made under
tropical conditions. This opportunity to test the effects of excessive hu-
midity and heavy static upon the equipment has proved useful in suggesting
the precautionary measures necessary in further tropical flights.

Longitude-effect. The longitude-effect was computed from counter-flight
observations made in Peru, as compared with flights made by Millikan and
his collaborators with electroscopes in India. This effect, reported by Mil-
likan as about 4 per cent at sea-level, was found to be about 25 per cent at
the point of maximum cosmic-ray intensity in the stratosphere. This value
is in good agreement with the figure calculated by T. H. Johnson from an
analysis of the energy-distribution of the primary rays.

Cooperation with Dr. T. H. Johnson. A project for making flights in
cooperation with T. H. Johnson was undertaken. A summary of the results
of this work is also given in the report by T. H. Johnson. The purpose
of this program was (a) to develop the single counter as an instrument for
measuring cosmic radiation, comparable in accuracy with an electroscope,
and (6) to use the counter so developed for a series of measurements. To
accomplish this purpose, further development work was done during Janu-
ary, February, and March 1938 on the technique, and the accuracy obtain-
able both in pressure and in cosmic-ray intensity measurement was con-
siderably improved.

Receiver technique. A new amplifier was designed and built, which
enabled an ordinary commercial receiver to be used for this work. The new
arrangement is particularly free from undesirable effects due to electrical
noise and static, and hence permits reception under conditions hitherto im-
possible. A new tape-register was also built, giving a record which can be
read with greater accuracy and ease.

Barograph. The barograph-system used in previous flights in Washing-
ton and Peru was further improved, both in accuracy and in reliability.
Careful tests were made for reproducibility of results and for constancy
of characteristics over periods of time.

Cosmic-ray meter. The new circuit described in the report of T. H.
Johnson was adapted to the transmission of scaled impulses from a large

378 CARNEGIE INSTITUTION" OF WASHINGTON

single counter, yielding an accuracy considerably greater than that pre-
viously attained.

Flights at Swarthmore. A series of eight flights was made at Swarthmore,
Pennsylvania, using the improved technique, during April, May, and June
1938. Altitudes up to 80,000 feet were attained, and one flight remained at
66,000 feet for eight hours. The results have yielded measurements of
cosmic-ray intensity up to within 2 per cent of the top of the atmosphere,
with an accuracy hitherto attainable only with electroscopes. The results
show a rapid increase in the intensity of the cosmic radiation between alti-
tudes of 25,000 and 60,000 feet, and that the ionization reaches a maximum
at a little above the latter elevation. The measurements of the rate of in-
crease are in good agreement with those reported by Millikan using electro-
scopes. One of these flights was made during the latter portion of a severe
magnetic storm. The results showed that, as the magnetic field-strength
was returning to normal, no measurable effect was observed in the cosmic
radiation. The development of the technique has been carried to the point
where flights may be made as a matter of routine.

Cooperation. It is a pleasure to acknowledge cooperation received from
the National Bureau of Standards and from Dr. T. H. Johnson in connection
with the cooperative programs described above. Advisory assistance re-
garding balloon technique was received from the United States Weather
Bureau. To the Peruvian government, and especially to Dr. G. A. Wagner,
Director of the Peruvian Meteorological Service, are due thanks for assist-
ance of the utmost value with the observations made in that country. For
assistance in Panama the author is indebted to Dr. J. Zetek. Helpful assist-
ance with various phases of the work has been received from J. A. Fleming,
W. F. G. Swann, S. E. Forbush, and many others. Acknowledgment is also
made to the Commander of the U. S. S. Icarus, to Dr. E. A. Abbey, and to
others who have cooperated in returning to us our instruments recovered
from flights, together with complete data regarding the circumstances of
finding them.

Millikan, Robert A., California Institute of Technology, Pasadena, Cali-
fornia. Studies of cosmic rays. (For previous reports see Year Books
Nos. 31-36.)

The results obtained between July 1, 1937 and June 30, 1938 in the cosmic-
ray studies carried on at the California Institute of Technology with the aid
of funds supplied by the Carnegie Corporation of New York administered
by the Carnegie Institution of Washington may be very briefly summarized
as follows:

Studies of Bowen, Millikan, and Neher on the total cosmic-ray energy
entering the atmosphere at six different latitudes as determined by the
ionization in electroscopes carried by balloons practically to the top of the
atmosphere. 1. The rate at which cosmic-ray electrons of energies between
6.7 billion electron-volts and 17 billion e-volts enter the atmosphere is one
such shot every 11 seconds per cm2.

physics 379

2. The total cosmic-ray energy brought to the earth by all entering elec-
trons of energy smaller than 6.7 billion e-volts is but two-thirds of that
brought in by the foregoing band of entering electrons.

3. The total cosmic-ray energy brought to the earth by all entering elec-
trons of energy higher than 17 billion e-volts plus that brought in by all
photons of all energies is but 8 per cent larger than that brought in by the
electron band described in (1).

4. Cosmic-ray electrons then come into the Earth as a limited band of
energies, which band has a maximum at from 6 to 7 billion e-volts. This
band has the range of energies to be expected if the total mass energy of the
atoms of the only abundant elements save hydrogen and helium could be
transformed in toto into two oppositely directed cosmic rays. Hydrogen
and helium would be largely cut out anyway by the Sun's magnetic field.
See (6) below.

5. The smallness of the number of entering photons (see 3 above) requires
that the entering rays cannot have come through an appreciable amount of
matter in comparison with an atmosphere in traveling from their place of
origin to the Earth, and hence that they cannot have originated within the
stars or in any portions of the universe in which matter is present in appre-
ciable abundance.

6. Dr. Paul Epstein by a careful analysis of the effects on cosmic-ray
electrons of the Sun's magnetic field has shown that if that field at the Sun's
surface has a value of 25 gauss, no electrons of less than 1.6 billion e-volts
can reach the earth. No additional electrons should therefore be found
entering the Earth's atmosphere north of 58° north magnetic latitude, in
agreement with the results of the foregoing balloon flights.

7. Cosmic rays can be thus used to set an upper limit to the value of the
Sun's magnetic field. Thus the often assumed values of 40 or 50 gauss are
now found impossible since no additional electrons could then reach the
earth north of Omaha, 51° magnetic latitude, where many are found by
Bowen, Millikan, and Neher.

Studies of Carl D. Anderson, Seth Neddermeyer, and assistants by Wilson
cloud-chamber techniques on electrons and penetrating charged particles of
intermediate mass between electrons and protons appropriately named meso-
trons (intermediate particles). By building a cloud-chamber in which one
of the two activating tube-counters is inside the chamber it has become
possible to catch cosmic-ray particles at the very end of their ranges. With
this new apparatus 10,000 cosmic-ray photographs have been taken. One
very remarkable photograph shows a "dying cosmic ray," a mesotron which
ended its range in the gas itself and which has a range and curvature con-
sistent only with a mass of about 240 electron masses. This furnishes direct,
unambiguous photographic proof of the existence of these new particles
discovered in a series of Anderson-Neddermeyer researches extending from
1934 to 1937.

Anderson and Neddermeyer are now experimenting with very large cloud-
chambers in the hope of increasing largely the resolution in the measurement
of mesotron masses, one of the most vital problems of the new nuclear
physics.

380 CARNEGIE INSTITUTION OF WASHINGTON

Neddermeyer has published a theory in which mesotrons are considered
to be higher mass states of ordinary electrons, possessing possibly a series of
different masses.

Mr. Vargus, assisting Anderson, has measured the angle of scattering in
traversing a 1-cm platinum plate of 361 particles of energies above 500,-
000,000 e-volts and obtained within this range scattering angles agreeing
with the Mott-Williams scattering formula. In lower-energy ranges, how-
ever, the observed scattering is about one-half the theoretical.

Mr. Boggild has developed a counter to be used inside a chamber for
absorption-measurements in a very light element in order to determine
(a) what is the mechanism of electron-absorption in addition to pair forma-
tion and ionization along the track, (b) what are the relative numbers of
electrons and mesotrons to be found in the lower-energy ranges, and (c)
whether the mesotron has a unique mass, and whether it is possible to
determine its mass more accurately.

Neher and Pickering: development of a Geiger counter of very high reso-
lution for cosmic-ray balloon work. Successful daily flights made over a
period of ten months at Burbank, California, using radio meteorographs
made at the California Institute of Technology, have resulted in reliable
transmitting and receiving equipment which uses a wave-length of but 1.6 m.
This wave-length is so short as to be free from the usual local disturbances
which have hitherto impeded progress in the receipt of radio meteorograph
signals from balloons. Neher and Pickering have adapted these techniques
to the problem of sending signals from a pair of vertical Geiger counters
carried up by balloons and activated by cosmic rays.

To gain accuracy they have developed Geiger counters of large cross-sec-
tional area (5 by 2.75 inches). These have about ten times the area and will
therefore give ten times the counting rate of any counters used heretofore
for balloon work. The counters have a time of reaction of less than 10-5
sec. It is necessary therefore to use only two counters even of this large
diameter for coincidence measurements in order to have a very small number
of accidental counts. The efficiency is also 100 per cent to within an accuracy
of 1 per cent with a background counting rate of 30,000 per minute. This is
approximately the number of background counts to be expected as a maxi-
mum on a flight. The data for a flight will therefore need no correction
either for loss of efficiency or for accidentals.

The recording mechanism has been successfully worked out so that both
the barometer and the signal from the counters are recorded in a permanent
form.

The maximum counting rate to be expected from two Geiger counters
counting coincidences due to particles coming mainly from a cone of 30°
about the vertical is from 800 to 1000 per minute. An average over a period
of five minutes will therefore give a probable error of ±1 per cent. This is
comparable with the accuracy attainable with the present balloon electro-
scopes, and very much higher than in preceding counter measurements.

Preliminary flights are expected to be made within the next few months.

PHYSICS 381

Epstein, P. S., and G. W. Potapenko, California Institute of Technology,
Pasadena, California. Study of influence of the earth curvature on the
propagation of short electromagnetic waves.

The grant made by the Carnegie Corporation of New York and admin-
istered by the Carnegie Institution of Washington for study of reception of
micro radio waves has been used to determine as accurately as possible the
intensity of waves transmitted over various distances. The comparison of
the results with the theoretical values will give a measure of the secondary
effects omitted in the theory (such as absorption of the atmosphere, etc.).

The two wave lengths of 5 m and 1 m were selected as the most promising.
In either case the apparatus was designed to consist of three portable units:
(a) the power pack with specially designed stabilizers; (6) the transmitter
or oscillator; (c) the receiver or field strength meter. To insure an easy
variability of the distances, it is intended to set up the power pack and
transmitter on the shore of the Pacific and to mount the field strength meter
on a boat.

On June 30 the state of work on the project was as follows:

5-m waves. All three units of the apparatus (including a frequency
stabilizer of standing wave type for the transmitter) are completed, tested
in the laboratory, and ready for field work.

1-m waves, (a) The power pack is completely built. It contains an
elaborate voltage stabilizer of special construction which will be described
elsewhere, {b) The transmitter is designed, its parts built, and ready for
assembly, (c) The field strength meter is designed but not yet built.

Committee on Study of the Surface Features of the Moon. Progress
report for the period July 1937 to June 1938. (For previous reports
see Year Books Nos. 26-36.)

During the past year the series of measurements by visual methods on the
plane polarization of sunlight diffusely reflected by different areas on the
moon's surface and by different terrestrial materials has been completed and
the report on the work is in preparation. The results indicate clearly that
the materials exposed on the moon's surface are of light, porous nature and
produce polarization effects similar to those observed in sunlight diffusely
reflected by pumice and volcanic ashes high in silica.

Progress has been made with methods other than visual for measuring
the percentage amount of polarization in diffusely reflected sunlight. These
include: (a) A vacuum thermoelement used with a special Wollaston prism
of quartz and with a lens system of fused silica. It has not been possible
heretofore to obtain with this method the degree of sensitivity necessary for
the purpose, (b) A polarization spectrograph consisting of fused silica
optical parts and a Wollaston prism of quartz. The results obtained with
this instrument have not been entirely satisfactory and further work with it
will be necessary to obtain the desired degree of sensitivity. It should prove
to be of greatest value in the ultraviolet and near infrared parts of the
spectrum, (c) A photoelectric cell in a direct current circuit similar to that
employed by Dr. Joel Stebbins in stellar work and used with a special Wol-

382 CARNEGIE INSTITUTION OF WASHINGTON

laston prism of quartz. This apparatus is still in the experimental stage;
but the results obtained with it are promising, (d) A rotating polarizing
prism used together with a photoelectric cell and a special new high-gain
alternating current amplifier designed by Dr. Ellis Johnson of the Depart-
ment of Terrestrial Magnetism, and constructed in its workshop. The maxi-
mum sensitivity of this amplifier is attained at a frequency of 10 cycles per
second or a rotation period of the polarizing prism of % second. The new
apparatus has been assembled and preliminary tests indicate that its sen-
sitivity is high; theoretically the apparatus should measure the amount of
polarization to 0.1 per cent. The Moon Committee is indebted to the De-
partment of Terrestrial Magnetism for the development of the new amplifier.

In connection with the study of the physiography of the moon's surface
it is essential to obtain more information than is at present available on the
shapes and relations of its different topographic features. As the result of
studies by selenographers during the past three centuries the heights of
many of the mountains and the depths of many craters have been measured
by several different methods; but each measurement has required tedious
computations to derive the desired information. So much labor is needed to
obtain results by these methods that several years ago the Moon Committee
devised a new method for the purpose ; this grazing-incidence method prom-
ises to yield valuable information. It is based on a simple relationship.
If the angle of elevation of the sun's rays at a given point on the moon's
surface be known at a given time, then a given slope will cast a shadow if its
slope angle exceeds the angle of elevation ; if its slope angle is less, the slope
will be illuminated; if its slope angle is equal to the angle of elevation, the
phenomena of grazing incidence will be observed. If a series of photographs
taken at frequent intervals during a lunation were available, inspection of
these photographs would enable the observer to ascertain the time, for
any given slope, at which the incident sun's rays just begin to illuminate
the slope.

It is possible with the aid of the Nautical Almanac and Ephemeris to as-
certain the phase angle (angle at the moon's center between the lines of
sight to the centers of the sun and the earth respectively) for the instant of
time at which a given photograph was taken. With aid of an accurate per-
spective projection chart the angle of incidence of the sun's rays at any
point on the moon's surface and for any given phase angle can be read off
directly from the chart without computation. From the same chart, printed
on celluloid and superimposed on the negative or a print therefrom, the
dimensions of any lunar surface feature can also be read off directly in
terms of angles and these in turn converted to linear dimensions by use of a
small table. By this method the observer is in position with a sufficiently
complete set of photographs to reconstruct the shapes, both in plan and
section, of lunar surface features not too far (less than 45°) from the center
of the moon's disk and to draw therefrom a rough topographic map.

The Moon Committee is fortunate this year in having assigned to its use
the 100-inch telescope for photography of the moon during the July luna-
tion. The first photographs were taken on June 30, 1938, and are to con-
tinue throughout the lunation until July 24. During this period it is planned

physics 383

to take photographs on different types of plates at intervals of 5 or 10 min-
utes during periods of good seeing. It is expected that the series of photo-
graphs taken at the Newtonian focus with the aid of the zero corrector lens
will form the basis for detailed studies of the topography of many surface
elements of the moon. The zero corrector lens may be successfully used
between wave lengths 5000 to 6000 Angstrom units; beyond these limits
chromatic aberration becomes serious. A yellow filter of glass of charac-
teristics approximating Wratten K2 is used and sensitometer spots through
the filter are imprinted on each plate. To reduce halation each plate is
backed. The following plates are to be used: Eastman Spectroscopic C3,
D3, F3, Solar Green A, and Wratten and Wainwright panchromatic; they
are to be developed in the soft Ross elon developer.

On February 1938, the Committee suffered severe loss through the un-
expected death of one of its members, Dr. F. G. Pease, who took great in-
terest in the surface features of the moon and in 1919 with the 100-inch
telescope procured at its Cassegrain focus the best photographs of the moon
that have thus far been obtained. It was in part his enthusiasm for the
subject that led to the appointment of our Committee. Dr. Pease gave
freely of his time and thought to our work and we shall greatly miss his
genial personality and helpful support.

W. S. Adams

J. P. BlJWALDA

A. L. Day

P. S. Epstein

E. Pettit

H. N. Russell

F. E. Wright, Chairman

PHYSIOLOGY

Russell, G. Oscar, Ohio State University Speech, Voice Science, and Hear-
ing Research Laboratories, Columbus, Ohio. Physiological cause of
voice quality differences. (For previous reports see Year Books Nos.
28-33, 35.)

Studies have continued with aid of funds provided by the Carnegie Cor-
poration of New York to the Carnegie Institution of Washington.

Some of the more basic facts uncovered in this study are beginning to
have their effect on the scientific literature pertaining to the mechanism of
the larynx and sound-producing organs in the human being. The last edition
of Cunningham's Anatomy, for example, points out for the first time that the
ventricular bands are capable of constriction independently of any move-
ment in the glottal lips proper. It will be remembered that this was one of
the facts which grew out of our vocal cord motion pictures. Since the
demonstration was so new and had not been made before, and the observa-
tion was so diametrically opposed to previous concepts, it aroused consider-
able skepticism, at first, except among those who actually saw the film.
However, Dr. Leon Strong of the Department of Anatomy at the University
of Michigan was induced thereby to undertake a careful histological re-
working of the area, which has thrown considerable additional light on the
subject.

As has been indicated in our previous reports, these activities in the
superior larynx, including those of the ventricular bands, seem to be pri-
marily responsible for a major part of voice quality distinctions. Yet most
of these functions which can now be observed and studied directly, by
means of the techniques devised in this investigation, not only have hereto-
fore not been noted even in books on anatomy and physiology, but in many
cases have been indicated as impossible. The function just referred to was
one of these. Since the ventricular bands have their attachments on the
same cartilages as the glottal lips, it could not be seen how one set could
function independently of the other.

The pulvinar, cartilages of Wrisberg, and other parts of the superior
larynx are also just as radically involved, as we have previously stated. As
yet, however, others have given practically no attention to these functions.

That the pulvinar can function quite independently of movements in the
superior epiglottis seems to be definitely established by the experiments we
have thus far performed. We have just initiated a study this year of the
physiological action which appears to be there involved. It is not yet in a
state where it can be released in article form. Suffice it to say that the
muscular contraction which brings about this posterior movement seems to
be from above, down as well as back. And the visible posterior termination
of the contraction appears to fall just above the ventricular bands forward
of the arytenoid cartilage. However, this contraction takes place without
involving the upper edges of the epiglottis proper, which in this study have
been shown to contract very violently at times, but may in this case remain
quite relaxed. That would seem to indicate a function of the arymembrana-
ceous muscle.

384

PHYSIOLOGY 385

Certain very low pitch changes are apparently in part likewise accom-
plished by means of this posterior movement of the pulvinar. It often seems
also to be involved in the creation of some guttural qualities. And to a cer-
tain extent the opposite type of loud strident and nasal twang qualities seem
to be abetted through its partial involvement. The same may be said of
those asthenic qualities in the voices of certain individuals, giving what
in the past has been classified as "lack of resonance." For if pulled lightly
over the voicing glottal wedges the pulvinar appears to serve much as would
a soft sponge clamped over the mouth: the voice escapes, but it lacks that
"vibrant ringing" quality so often erroneously called "resonance"; and if
the sponge occludes the opening too completely, the voice is muffled.

From the beginning it appeared, however, that the major part of voice
quality differences was created by the glottal lips themselves. About all we
could see was what appeared to be a variation in the thinness or blunt
roundness of the interior glottal margin of the lip itself. And that was
hardly enough to establish the observation. Actual proof of quality differ-
entiation in the glottal tone was needed.

For some time we have been seeking unsuccessfully to obtain such facts.
We sought to contact, through laryngologists, a case or two in which open
unhealed wounds immediately superior to the glottis would make possible
a direct study of the tone as it emits from the vocal source before it passes
through the pharyngeal, buccal, and nasal cavities above. For some proof
would thereby be made possible. If the sound could be conducted out
directly and the pharynx, mouth, and vocal cavities above be cut off entirely,
it would be possible to make oscillographic photographs of the isolated
glottal tones which would demonstrate whether any part of the vowel or
voice quality was produced in the larynx rather than by intervention of the
resonating cavities above. The latter is of course the assumption all but
universally made.

In 1872 Dr. E. M. Moore of Rochester, New York, reported such a case
in one Edward Matthews.1 The patient had attempted to commit suicide by
slashing his throat immediately above the thyroid cartilage, and at the base
of the epiglottis. The edges of the wound cicatrized so that it failed to close,
leaving an oval opening two inches long by three-quarters of an inch wide.
Dr. Moore reports that when he threw the patient's head back and inserted
a sheet of buckskin so as to prevent any possibility of sound passing into
the mouth and head cavities above, most of the vowel qualities could be
easily created. Only the consonants were badly impaired. This would indi-
cate that certain qualities are created right in the larynx proper.

Furthermore, we were successful in contacting an individual from whom
had been removed all those cavities which have in the past been given the
credit for creating this so-called "resonance." He was a patient of Dr.
George M. Dorrance in Philadelphia. All the sinus and other open cavities
above the velum and palate had been completely removed. There remained
nothing but one wide megaphone-like opening in the head where they and
the nose should have been. We took over a number of voice teachers and
acoustic scientists from the convention of the Acoustical Society to observe

1 E. M. Moore, Trans. New York State Med. Soc, 1872, pp. 276-282.

386 CARNEGIE INSTITUTION OF WASHINGTON

the case. All were agreed that the carrying power of this individual's voice
was certainly not impaired. On the contrary, the loudness of the voice,
when the velar sphincter was left open, was, if anything, greater than in the
normal individual. That indicated that this phase of so-called "resonance in
the voice" is certainly not traceable to any sinus functioning as a resonator
to add carrying power to the vocal tone. For every paranasal sinus in this
man's head was gone.

Mr. Warren, working with us in the summer session at the University of
Wisconsin, is approaching this problem in a different way. He is using an
artificial larynx sealed into a cadaver head and making an oscillographic
photograph of the resulting tone as he fills up each sinus and varies the
size of the ostrium and enlarges accessory openings into these nasal so-called
resonators. The curve will show whether any change in loudness or quality
is created when a sinus is first left normally open, and then filled up with a
solid substance. Our first tentative results in three experiments showed no
change whatever in the curve. In other words, neither loudness nor quality
was changed when the sinus was filled up.

But all this still leaves unsolved any confirmation of Dr. Moore's observa-
tion that vowel, much less voice, qualities might be created right in the
larynx.

Our major experiments this year have revolved around this question. We
devised experiments, making use of our resonometer contact transmitter
described in one of our previous reports, to show whether any quality dis-
tinctions could be detected right at the vocal cords as the subject produced
different vowels. When coupled with a high-powered amplifier feeding into
a cathode ray oscillograph, the resonometer transmitter will show the
slightest variation of quality traceable to either harmonic or inharmonic
tonal partials present in any vibrating surface it touches. But it will not
respond to any vibration in the air.

Since the contact button is only about half the size of a dime, if it is placed
in contact with the throat on the exterior, right at the point under which
lies the glottal lip (or vocal cord), it follows that if any variations in the
sound patterns occur as one passes from one vowel or one voice quality to
another, absolute evidence is produced showing that the quality vibrations
within the glottal lip itself are changing. In other words, the harmonic
components in the tone resulting from glottal lip vibration are different, and
may be modified at will within certain limits.

It was quite necessary that we be able to make a sound movie record of
the subject's face simultaneously with this resultant of the point of contact.
Then any variations in the exterior buccal aperture, as well as of the sound
track produced by the vocal cavity air-bone vibrations, could be studied
as they correlated with the glottal tone shown in the curve on the oscillo-
graph photograph on the same frame with the subject. A large number of
such records have been made for us in sound pictures of the subject which
we were successful in finally getting completely synchronized with the
oscillographic track appearing right on the same frame. This gives us,
therefore, the sound emanating from the mouth with its harmonic compo-
nents accurately enough recorded to make clear distinction as to exactly

PHYSIOLOGY 387

what vowel was being produced. This track may thereupon be compared
with the contact resonometer oscillograph curve appearing alongside, which
of course shows the tone produced in the larynx right at the vocal cord itself.

While the experiments are not yet complete and will necessitate careful
study over several years to come, they seem to produce definite evidence
that the glottis (rather than the so-called "resonating head cavities") is
primarily responsible, first, for the loudness or carrying power of the voice;
second, for a substantial part of the vowel quality distinctions; and, third,
for much of the voice quality differences we hear.

We are well aware of the fact that these observations are in sharp conflict
with the viewpoints generally held to date, and that careful study of the
experimental evidence is required before one becomes too positive. So, for
example, it is very obvious that both the vibrating source and the natural
frequency characteristics of the cavities being stimulated thereby will be
respectively modified when the two are coupled. Hence, if one records the
curve produced by the vibrator, they may well show changing character-
istics due to coupling with cavities above which alone are being modified.
But this fact is quite as important to know; and it is one which has been
entirely overlooked in all previous considerations of the physiological cause
of voice quality differences. Furthermore, it would still be a glottal tone
change. Besides, it can even now be tentatively said that the curve char-
acteristics in the glottal tone as picked up by the resonometer are so radically
different from voice quality to voice quality, and from vowel to vowel, as
to make it very doubtful whether the coupling effect can be assumed to be
by any means entirely responsible.

The major part of our activities has been devoted to life-size reconstruc-
tion in hard plaster and resilient cast of the exact vocal organ position used
by Lawrence Tibbett in the production of different vowels, pitches, and
voice qualities. By this means one begins to get a better understanding of
relationships, and their effects in the actual human being. This reconstruc-
tion can be made accurate to within the width of a pinhead by reason of our
X-ray and laryngoperiskopik photographs controlled to within a 0.1 mm.
possible deviation. Through the N. Y. A. Board we have been provided
with three to six helpers who were untrained in the beginning, it is true,
but have gradually become of considerable assistance. This help has of
course been without cost to the project. Our major expense this year has
been for the sound pictures, but that has been relatively nominal. So that
again it has been possible for us to conserve the major part of our funds.
Since our two principal projects represent entirely new experimental tech-
niques which had to be perfected, no articles have been published thereon
except two of Dr. Robert 0. L. Curry.1

1 Robert O. L. Curry. The cathode-ray oscillograph in speech recording and analysis.

Jour. Scientific Inst., vol. 11, no. 5, pp. 162-164 (1934). Printed in Great Britain.

Idem, The mechanism of pitch change in the voice. Jour. Physiol., vol. 91, no. 3, pp.
254-258 (1937). Printed in Great Britain.

PSYCHOLOGY

Ruger, Henry A., Teachers College, Columbia University, New York, New
York. Studies of correlational surfaces. (For previous reports see
Year Books Nos. 27-36.)

These studies have been continued with funds made available by the
Carnegie Corporation of New York to the Carnegie Institution of Wash-
ington.

The work of the past year was concerned mainly with the transfer of
higher moments and higher product moments from arbitrary origins to true
means. This was completed for four pairs of traits. These were weight
and span, stature and span, pull and stronger grip, and sitting height and
stronger grip. Forty-one moments and product moments were computed
for each age group for each pair of traits. Fifteen consecutive age groups,
those from 16 to 30, were employed. In addition, the forty-one moments
and product moments about arbitrary origins and for each of the age groups
were computed for five more pairs of traits. These moments have been
referred to true means in about one-fourth of the total of such operations.
A study of the fluctuation and trends of these moments with age and of
their relation to corresponding values in the population of 7000 males is. to
follow. Despite the fact that all scores are residuals from regressions,
nonlinear, on age, such trends appeared in the case of correlation coefficients,
correlation ratios, regression coefficients, and simple product moments as
shown in the earlier studies of this series, Annals of Eugenics, vol. 5, pts. 3
and 4. This was true of certain pairs of traits and not of others. The present
study is concerned with the behavior of higher product moments under like
conditions.

An average force of ten statistical workers under the supervision of, at
first, Antonia von Brand and now of E. K. von Brand has been furnished by
the Works Progress Administration.

388

ST. AUGUSTINE HISTORICAL PROGRAM

Chatelain, Verne E., St. Augustine, Florida. The St. Augustine Historical
Program. (For previous report see .Year Book No. 36.)

Financial aid for support of these studies has been supplied in part from
funds made available by the Carnegie Corporation of New York for study of
problems relating to factors involved in the history of the United States.

The St. Augustine Historical Program completes the second year of its
investigations and research with the preparation for publication of the first
of a series of studies on the First Spanish and British periods, bearing on the
problem of military fortifications and defense strategy in relationship to
other elements of growth and development in the region controlled by the
Presidio de San Agustin. This study appears in two parts, the first a section
of text treating of the defenses chronologically stage by stage as related to
the general processes of Spanish and British colonization; the second part is
a map atlas which will include, with an introduction and editorial comment,
a considerable number of hitherto unpublished manuscript maps principally
drawn from Spanish and British archives. In addition, there is already in
the course of preparation another general study, analyzing and contrasting
the agrarian and colonial policies of the Spanish and British in Florida.

Since the completion of the preliminary survey in March 1937, the staff
of the St. Augustine Program has worked steadily at the task of discovering,
collecting, and studying the great mass of written source materials existing in
this field of American history. Many of these materials are parts of foreign
archives, and to date the work has been centered largely upon surveying and
dealing with special collections of photostats and transcripts to be found in
public and private libraries in America, such as the Lowery, Connor, Brooks,
Stetson, and Buckingham Smith materials; and the special series in the
Library of Congress and the Clements Library involving the East Florida
Papers, the Papeles Procedentes de Cuba, the papers of the Audiencia de
Santo Domingo, the British Public Record Office, the British Museum, and
the Gage, Haldimand, Clinton, and Shelburne documents, some of them
originals, and some transcripts or photostats. Mention should be made
also of very considerable map collections with which the staff has concerned
itself, located primarily in the Library of Congress and the Clements
Library.

Along with this program of research, substantial progress has been made
in the field investigations at St. Augustine bearing upon the location, present
condition, classification, and history of numerous sites associated with the
various events and stages of growth in that area. Since the beginning of the
St. Augustine Program, combined historical and archaeological techniques
have been used in this phase of the work, and these methods have been
gradually perfected in meeting the actual conditions of the Program. Mr.
Albert Manucy, assistant historian, and Mr. W. J. Winter, archaeologist, have
had this activity in charge.

A system of "case histories" has now been developed to a point where,
with regard to many sites, it is possible to say with some degree of certainty
just what has happened through successive stages of history. These case

389

390 CARNEGIE INSTITUTION OF WASHINGTON

studies are made for house sites, fortification elements, and other sites where
important events have taken place, but where perhaps there are no remains
of human structures. Thus the historical and descriptive data include de-
tailed information about the succession of ownership of property, legal
descriptions of sites, related environments, and in many cases now fairly
complete archaeological studies, with field notes, maps, photographs, sketches,
and engineering data. A recent study of Fort Picalata, one of the outlying
defenses of St. Augustine, is a case in point.

Inasmuch as the St. Augustine Program involves not only historical re-
search, but also the development and use, under the best possible conditions,
of existing physical remains of history, these local studies and resulting
data on individual sites and structures are especially important in establish-
ing the standards and basis for future civic activity. In this connection, a
notable achievement of the past year has been the adoption by the City of
St. Augustine, under the authority of an act of the Florida Legislature,
of a zoning ordinance, which has as its principal objective the perpetual
preservation and control of the physical elements of history within a
suitable environmental condition. This zoning measure is a distinctive
civic achievement and goes so far beyond the standards generally pre-
vailing today in American communities that it stands without precedent
in the field of activity for the preservation of historic sites, and points the
way to many possibilities in dealing with such situations.

Commendable progress is now being made upon the preparation of detailed
plans or projects for the physical treatment of many of the individual his-
toric sites in St. Augustine. These include architectural, landscape, and
general environmental considerations, all seeking to emphasize the preserva-
tion and wise use of the historical elements. Among other things accom-
plished, a complete system of historical markers has been prepared, and is
soon to be installed ; the local staff has been in charge of the preparation of
these markers, as well as of their proper location.

Intensive study has been given during the past year to the entire system
of inner defenses, including the three northern lines or parallels. This work
has involved an adaptation of the method of case study, suggested above,
to more general areas, rather than particular sites. Since St. Augus-
tine during all the Spanish and British periods was primarily a military
presidio, this element in the study deserves special emphasis, and must
always be taken into consideration in dealing with other problems of com-
munity growth.

In so far as its scope and methods are concerned, the St. Augustine Pro-
gram has been closely connected from the beginning with other activities
now being carried on by the Institution. The approach at St. Augustine con-
tinues to be on the basis of cooperation in use of information from all
branches of science and history that can contribute. Illustrative of this point
is the fact that special studies in medical history are now under way under
the auspices of the St. John's County Medical Society; also certain linguistic
and group culture studies, bearing on the Minorcan element, have been under-
taken under the sponsorship of the Spanish Institute of Florida and the St.
Augustine Historical Society.

ST. AUGUSTINE HISTORICAL PROGRAM 391

Finally, it may be noted that many of the earlier objectives of the his-
torical program of Carnegie Institution of Washington, having to do with
the use of new materials and with the study of the beginnings of American
colonization, are being furthered by the studies now going forward in the
St. Augustine Program. The work, now ready for publication, dealing with
the military frontier and its defenses, and that in the process of preparation,
bearing upon the analysis and comparison of the early Spanish and British
colonization systems, may contribute to other studies of early American
history.

SEISMOLOGY

California Institute of Technology. Report on cooperative researches
at the Seismological Laboratory, Pasadena, California.

Although the active direction of the Seismological Laboratory at Pasa-
dena passed on January 1, 1937 to the California Institute of Technology,
operating through a committee consisting of Dr. John A. Anderson, Mr.
Harry 0. Wood, Dr. Peno Gutenberg, and Dr. John P. Buwalda, Chairman,
no extensive change has occurred in the program of research of the Labora-
tory and in the personnel conducting it from that date to the end of the year
under review, June 30, 1938. The recording and the study of the records
of local earthquakes, a program undertaken when the Laboratory was
founded, continues to absorb the larger part of the effort of most of the
members of the staff and of the funds available. This research program is
unique in that in most seismological laboratories of the world major atten-
tion is given to teleseisms or distant earthquakes. The attention of the Pasa-
dena Laboratory, with its six outlying stations scattered through southern
California, has been concentrated during the past decade not merely on the
more important earthquakes occurring in this region but on shocks of all
magnitudes, the barely registerable disturbances commonly contributing
data of value comparable to those derived from more important ones. This
very intensive study has yielded an enormous amount of data bearing on
such questions as the distribution of seismic activity of the different parts
of southern California, the relation of earthquake origin to the active faults
of the region, the depths of the foci of shocks, the waxing and waning of
the activity in particular localities, the relation of epidemics of minor shocks
to stronger earthquakes, the energy dissipated in large and small shocks,
the differences in velocity of earthquake waves in different types of rock
and in different directions along and across the major structures of the
country, the amplitude and period of oscillation in different parts of an earth-
quake, and the nature of the complex motion. These and related data are
of very great value to structural engineers in designing earthquake-resistant
buildings and other structures. While much of the effort is of course directed
toward the solving of various scientific questions relating to the nature and
causes of earthquakes, another major purpose in the accumulation of this
vast amount of information about local shocks and its interpretation has
been the contribution it makes to the only feasible solution of the problem
of safety in earthquake countries: the building of office, manufacturing,
residential, and other structures of such resistance that neither the shock
nor the conflagration which customarily follows it can destroy them. Safety
of buildings virtually means safety of life in earthquakes.

In addition to the local earthquake study much attention has also been
given to certain types of distant earthquakes, especially those with unusually
deep origins ; to the structure of the deep interior of the earth ; to the veloci-
ties of different types of waves through the interior and the reflections of
wave trains from the inner and outer surfaces of the shells of which the
earth is constituted; to the design and construction of a new type of seis-

392

SEISMOLOGY 393

mograph, and of a motion picture film recorder for seismographs, as well
as a considerable number of other new types of equipment.

Some of the activities of members of the staff of the Laboratory are sum-
marized in the following paragraphs.

Dr. Gutenberg and Dr. Richter completed an investigation, and published
the results, on the depth and geographical distribution of deep focus earth-
quakes.

The field operations involved in a determination of the depth of the fill
in Yosemite Valley and therefrom the form of the bedrock glacial trough
constituting the valley were completed by Dr. Gutenberg and Dr. Buwalda
and the results are being prepared for publication.

Dr. Gutenberg wrote several chapters for the bulletin "Physics of the
earth" being published by the National Research Council, and summarized
work completed with the California Institute seismic reflection equipment
in an article in "Ergebnisse der kosmischen Physik."

Much attention was given by Dr. Gutenberg during the year to further
investigation of the travel time and velocities of earthquake waves and to
the question whether travel times differ in different regions. With Dr.
Richter the so-called diffracted waves through the core were also studied,
and a new explanation for these waves was proposed, based on the assump-
tion that these waves are direct waves through the core. Besides studies
of records of earthquakes a theoretical study of this type of wave was also
made. In connection with this research the travel times of various types
of waves were revised by using data from deep focus earthquakes, and the
velocities of the waves in the interior of the earth were recalculated. They
seem to indicate that no discontinuity exists between a depth of 60 km. below
the surface of the earth and the surface of the core. Dr. Gutenberg and
Dr. Richter also investigated the effect of surface layers on the velocities
between the origin and points within 30° of the origin, in an attempt to
explain the observations that in the Montana earthquakes of 1935 the longi-
tudinal waves arrived several seconds too early at stations east of the Rocky
Mountains.

Dr. Gutenberg and Dr. Benioff undertook a research on pressure waves
in the atmosphere to determine whether they bear any relation to micro-
seisms. It was found that sometimes air waves with a period of a few sec-
onds occur, but the relation of these to microseism is not convincing. An
incidental result of this study was that it was found that the equipment
registered accurately the air waves produced by the target practice of the
Navy off the California coast, and using the data furnished by the Navy it
was found on calculating the velocities that the waves arrived late at the
Seismological Laboratory. It was concluded that the waves traveled in a
layer some 25 miles above the surface having a temperature above that of
the air at the surface.

Dr. Richter continued the study and the supervision of the measuring of
the local earthquake records during the year. Local seismic activity con-
tinued at about normal level, except that a gradual recrudescence of activity
in the Mojave Desert occurred, after a pause since about 1932. An increase
of small shocks was also noted in the Boulder Dam region, which may be

394 CARNEGIE INSTITUTION OF WASHINGTON

related to the weighting of the crust as a result of the filling of Lake Mead,
the reservoir behind the dam. The strongest shock in the southern Cali-
fornia region was one on May 31, 1938, originating in the Santa Ana
Mountains region, probably on the Elsinore fault. This disturbance was
felt over a large part of the southern part of the state but it did no damage.
Distant earthquakes are now being recorded and catalogued more com-
pletely than before, owing partly to the courtesy of the U. S. Coast and
Geodetic Survey in permitting study of seismograms being written at
Tucson.

Owing partly to the development of a fully equipped instrument shop
in the Laboratory, rapid progress was made during the year by Dr. Benioff
and his assistants in the design and construction of several new and im-
portant types of instruments, as indicated below.

New electromagnetic seismograph. A new electromagnetic seismograph
employing a moving conductor type transducer was developed. The inertia
reactor has a mass of approximately 100 pounds. The period is adjustable
from approximately 0.8 second to 4 seconds. Damping is electromagnetic
and is obtained from the reaction of the output currents. The spring is of
new type and is made up of a group of 12 flat steel strips acting in the form
of bent columns. The new seismograph uses either a ^-second or a 120-
second galvanometer for recording. The response is very nearly the same
as that of the Benioff variable reluctance seismograph, except at high seis-
mic frequencies, where the lower transducer impedance of the new form
results in a relatively greater response. The new instrument can be built
for approximately half the price of the older form.

Motion picture film recorder for seismographs. The relatively high cost
of photographic paper used in the local network of stations (approximately
20 cents per instrument per day) stimulated an investigation into the possi-
bilities of motion picture film as a recording medium for seismographs. Ac-
cordingly a film recorder was designed and built in the laboratory shop.
For the 30 X 90 cm. bromide paper the new recorder substitutes a strip
of standard 35-mm. motion picture positive film 90 cm. long. The recording
speed is reduced to % mm. per second and the line spacing to 1 mm. It was
necessary to substitute metal belts and pulleys for the final two sets of gears
in the drum rotation mechanism in order to eliminate variations in drum
speed caused by gear teeth. The cost per day per instrument with safety
film is approximately 4 cents as compared with 20 cents with paper. Mea-
surements on the film records disclose the unexpected finding that the accu-
racy is ten times as great as that of paper records.

Electromagnetic microbaro graph. An electromagnetic microbarograph
was developed for the purpose of recording atmospheric waves in the fre-
quency range 1/20 to 10 cycles per second. The responding element con-
sists of a moving conductor, permanent magnet, cone type, loudspeaker
unit. This is mounted over a circular hole in a sealed cubical container of
about % cu. m. capacity. Changes in atmospheric pressure thus produce
movements of the speaker cone with the result that electromotive forces are
induced in the speaker voice coil. The coil is connected to a standard seis-
mograph short-period galvanometer (^-second period) recorder, which re-

SEISMOLOGY 395

cords the currents. Although the instrument uses no amplifier its sensitivity
is sufficient to reach the level of general atmospheric unrest. Battleship
gunfire 160 km. distant has been recorded.

New recorders. A new type of recorder was developed and installed in
all the seismographs of the local network. In the new recorders the light
beam falls vertically from above on the top surface of the recording drum
with the result that the spot can be easily observed and adjusted in position,
focus, or intensity. The new recorders have been equipped with ballast
lamps for maintaining constant lamp current regardless of battery voltage
fluctuations.

Replacement and repair. New automatic radio recorders and new auto-
matic radio receivers for network synchronization were developed and in-
stalled in all stations. New automatic radio receivers for primary time
signals from Mare Island were developed in collaboration with Mr. F. E.
Lehner and have been installed in all stations. All stations were completely
rewired and overhauled. The Haiwee vertical seismometer was moved some
1700 feet to avoid vibrations due to a large pump in the vicinity of the
station. The recorder operates in the station and is connected to the seis-
mometer by a lead-sheathed cable. The portable seismograph assembly was
overhauled and a new radio installed. A N-S component strong motion
seismograph was installed. A spare 10-cycle drive for recording drums
was built. The construction of a measuring engine for film records is about
two-thirds completed.

OFFICE OF PUBLICATIONS *

Frank F. Bunker, Editor

In the report of the Office of Publications for last year (Year Book No. 36)
description and characterization of the publishing practice and program of
the principal administrative units of the Institution's organization was un-
dertaken.

The space limitations of the report were such that the organization and
work of but three of the major divisions could be sketched. These were: the
Division of Animal Biology with its lesser units of the Department of Em-
bryology, the Department of Genetics, the Nutrition Laboratory, and the
Tortugas Laboratory; the Division of Historical Research with its Section
of Aboriginal American History, Section of Post-Columbian American His-
tory, and Section of the History of Science ; and the Division of Plant Biology
with its many small groups of investigators studying various problems which
work in the plant sciences has developed.

It should be repeated that the regular staff of investigators of the Insti-
tution is organized in Departments and Divisions, each major unit being
engaged in coordinated study of related problems. In addition, a number
of investigators (Research Associates), affiliated with other agencies, are
pursuing specific investigations under short-term grants conferred by the
Institution. Some of the investigations made by the Research Associates
are conducted in close cooperation with the work of Institution departments.
Indeed, in some instances, the department head invites specialists in various
subjects to join his group for a time in order that some item of his depart-
mental program may be covered for which he is not suitably staffed. On
the other hand, in instances, the studies upon which the Research Associates
are engaged are independent of departmental programs and of departmental
supervision.

Reports on the progress of the investigations thus conducted are con-
stantly being published, some in monographic form for permanent record,
some in scientific journals and in the proceedings of scientific societies for
the current use of specialists, some in form suited to the audiences served
by the newspapers and the popular magazines, but all finding place, in sum-
mary or bibliography, in the Year Books of the Institution.

In the present report the sketch of the Institution's publishing practice
and program will be extended to embrace the remaining units of the staff
organization.

THE GEOPHYSICAL LABORATORY

Investigations to determine the modes of formation and the physical
properties of the rocks of the earth's crust were begun under the auspices of
the Institution in 1904, when grants were made for special researches to
be carried on in Washington at the office of the United States Geological
Survey.

In December 1905, plans for the erection and equipment of a laboratory
for the experimental work previously conducted by Dr. Arthur L. Day

1 Address: The Carnegie Institution of Washington, Washington, District of Columbia.
396

OFFICE OF PUBLICATIONS 397

were approved. A site of five acres on Upton Street in Washington was pur-
chased and a building suitable for the purpose was erected. In July 1907
Dr. Day, who had been appointed Director, and his staff took possession of
the building and began organizing the work which has been conducted con-
tinuously ever since.

The investigations undertaken by the Laboratory staff have included a
number of silicate solutions, corresponding to particular groups of rock-
forming minerals, and recently some in which water and carbon dioxide
have been associated.

Investigations have also been made of the quantity of heat involved in
mineral reactions and in the change of state from liquid to solid; also
in the study of solutions it has proved possible to show the manner of separa-
tion in magmas through differences in density between the minerals first to
crystallize and the remaining magma. It has even proved practicable to
approach certain active volcanoes and to make collections of the gases for
laboratory study.

So, also, the Laboratory has undertaken studies of atomic structure in
crystals; of the radium content of rocks from widely separated regions in
continental areas and also from samples taken from the ocean bottom; and
of the compressibilities of rocks and minerals and the effect of pressure upon
all the problems of mineral and rock formation.

Work in seismology was inaugurated by the Institution in 1921 with
appointment of an Advisory Committee, of which Dr. Arthur L. Day was
Chairman. Studies of earth movement in California have been undertaken
with effective cooperation of many agencies, and a new but extremely
simple type of seismograph has been developed. For the period from July 1,
1926 to January 1, 1937 the Institution, upon agreement, utilized the Seismo-
logical Laboratory of the California Institute of Technology for the initia-
tion and conduct of the seismological program in California. Since the
latter date, California Institute has been operating this Laboratory, the
Institution agreeing to continue financial support for a limited period.

The results obtained in the course of the investigations at the Laboratory
are in most instances published in the technical journals devoted to physics,
chemistry, ceramics, mineralogy, and geology. Although the researches
bear either directly or indirectly on geophysical problems, the individual
research is usually merely a phase of one of the more specific sciences.

Papers, when ready for publication, are sent in each instance to what is
believed to be the most appropriate journal, due regard being had for the
audience reached by the journal and the likelihood of publication. An
imposing number of technical journals are utilized in this manner. In-
deed, during the past three years papers from the Geophysical Laboratory
have appeared in no less than twenty-one regularly published journals and
three other publication mediums. Formerly, much use was likewise made
of foreign journals, especially the Zeitschrift fur unorganische una] allgemeine
Chemie in Germany, and the Philosophical Magazine in England.

Copies of the journals containing Laboratory papers are readily avail-
able in the libraries of the principal countries of the world and are received
by many scientific men as well. The distribution of papers prepared by

398 CARNEGIE INSTITUTION OF WASHINGTON

the staff of investigators is considerably increased through invitation sent
to a selected list of 1400 names, representing all parts of the world, to indi-
cate desire for reprints of the published papers. Abstracts of all the pub-
lished papers, now numbering 990, are also published in the Year Books
of the Institution.

When a series of researches is sufficiently advanced to form a reasonably
complete group they are issued by the Institution in monographic form.
Also, in several instances commercial publishing concerns have brought out
books dealing with subjects under investigation at the Laboratory which
were written by members of the staff.

THE MOUNT WILSON OBSERVATORY

The Mount Wilson Observatory was established in 1904, after a careful
test of atmospheric conditions at various promising points in California,
Arizona, and Australia had been made. The site selected is on the summit
of Mount Wilson, in Southern California, 5714 feet above sea level. The
laboratories, instrument and optical shops, and the offices for the measure-
ment and reduction of astronomical and physical photographs and for other
activities not requiring the favorable atmospheric conditions of the mountain
station are situated in Pasadena. From this point the summit of Mount
Wilson, twenty-eight miles distant by mountain road, may be reached in
one hour by automobile.

The Observatory was established for the purpose of studying the struc-
ture of the universe and the evolution of celestial bodies. The observa-
tional program comprises series of closely related investigations, so chosen
as to aid in interpreting one another, and all directed toward a common
objective. The underlying scheme is based upon an intensive study of the
sun, the only star near enough to the earth to be examined in detail.

The constitution of matter is also being studied in cooperation with the
Norman Bridge Physical Laboratory and the Gates Chemical Laboratory
of the California Institute of Technology.

Three telescopes are provided on Mount Wilson for solar observations:
the Snow horizontal telescope, the 60-foot vertical tower telescope, and the
150-foot tower telescope. These instruments were designed and constructed
by the Observatory staff to permit sunspots, prominences, and other phe-
nomena of the solar surface and atmosphere to be investigated under con-
ditions as favorable as those attainable in the study of artificial light sources
in the best of physical laboratories.

These three telescopes are used regularly for photographing the sun's
surface and its atmosphere; and for investigations of the solar vortices and
magnetic fields connected with sunspots, the general magnetic field of the
sun, the law of the sun's rotation, and the displacements of solar lines and
their bearing on the Einstein theory of relativity. The results thus obtained
have been of great service in the initiation and interpretation of researches
on stars and nebulse.

Four other telescopes, each equatorially mounted and provided with
special accessories, are employed for night observations. One of these is

OFFICE OF PUBLICATIONS 399

a 10-inch Cooke photographic refractor of 45 inches focal length, permit-
ting large areas of the heavens to be photographed on a single plate. The
other three are reflectors having apertures of 20 inches, of 60 inches, and of
100 inches, respectively.

The upper section of the tube of the 100-inch telescope is removable,
permitting several different optical combinations to be made by attaching
plane or convex mirrors, giving equivalent focal lengths ranging from 42 to
250 feet. Observations, almost exclusively photographic, are made from
observing platforms attached to the dome or to the telescope mounting, or
from within a constant-temperature laboratory, where a star image can be
formed by one of the combinations of mirrors. The great light-collecting
power of this telescope permits the faintest known stars to be photographed
directly on the sensitive plate and makes it possible to study a great number
of objects with aid of spectographs of high and low dispersion. The 100-
inch telescope is also especially adapted to the photographic and spectro-
scopic examination of nebulae, where minute details of structure are beauti-
fully revealed by its large-scale images.

These telescopes, in use throughout every clear night, are also employed
for the photographic measurement of the trigonometric parallaxes of stars
and nebulae, the determination of stellar motions in the line of sight, the
measurement of the distances and intrinsic brightness of stars by means of
the spectroscope, the determination of stellar magnitudes, the investigation
of star clusters and the scale of the stellar universe, the detection of changes
in nebulse and the measurement of their distance, and a great variety of
other studies.

Special attention is given by the Observatory to the invention and use of
new instruments and methods and the application in astronomy of devices
previously employed only in other branches of science. A notable illustra-
tion is the successful application of Michelson's interferometer to the meas-
urement of the diameters of several stars, some of which have been found
to exceed 300,000,000 miles. A 20-foot interferometer attached to the 100-
inch reflecting telescope was built for this purpose in the Observatory shops,
which are completely equipped for all classes of machine and optical work.
In order to extend the observations to smaller and somewhat fainter stars
an interferometer of 50 feet maximum aperture, mounted equatorially, has
been completed and is now in operation.

Another cardinal principle in the policy of the Observatory is the imita-
tion and interpretation of celestial phenomena by means of laboratory ex-
periments. The physical laboratory in Pasadena is provided with special
electric furnaces, flames, arcs, sparks, and vacuum tubes; apparatus for
producing intense magnetic and electric fields, high and low pressures, and
other devices for imitating the conditions existing in the sun, stars, and
nebulae ; together with spectroscopes of various types, echelons, Fabry-Perot
and Michelson interferometers, and auxiliary apparatus for analyzing the
light emitted under any desired conditions from controlled sources. The
laboratory equipment also includes a 500-kilowatt generator for experi-
ments requiring powerful direct currents.

The publications of the Observatory for the most part appear as papers

400 CARNEGIE INSTITUTION OF WASHINGTON

in the Astrophysical Journal. Reprints of these papers comprise a series
entitled "Contributions from the Mount Wilson Observatory/' and as such
are distributed, as issued, to a list of about 450 corresponding institutions
and individuals.

The "Contributions" include full discussion of individual problems, or of
definite phases of some larger problem, and detailed statements of the evi-
dence on which the conclusions are based. They consist of articles and
short monographs which first appear at irregular intervals in the Astro-
physical Journal and then are reprinted with continuous paging to provide
for subsequent binding in volumes of about 500 pages.

The arrangement with the Astrophysical Journal is such that the results
of investigations receive prompt publication and wide circulation, including
the regular subscription list of the Journal in addition to the list of cor-
respondents of the Observatory, at a cost considerably less than that which
independent publication would entail.

In addition to the "Contributions," brief preliminary statements, includ-
ing an outline of the evidence, covering the results of important investiga-
tions are published in the Proceedings of the National Academy of Sciences.
These "Communications," as they are called, are reprinted and distributed
to correspondents, as with the "Contributions." A "Communication" is
usually followed by an amplified treatment of the problem in question and
is accorded place in the "Contributions" series.

At infrequent intervals the Office of Publications of the Institution pub-
lishes monographs and catalogues which are too long for inclusion in the
"Contributions" series. These volumes are sent to the depositories of the
Institution and to special lists of correspondents, which vary with the sub-
ject material of the volume.

One such publication that is noteworthy has just been brought out in this
manner. It is: "Magnetic Observations of Sunspots," by George E. Hale
and Seth B. Nicholson. This publication, appearing in two parts, has been
in course of preparation for many years. It describes the solar telescopes
of the Mount Wilson Observatory and gives the history of their develop-
ment. In it the observations and theories which led Dr. Hale to discovery
of magnetic fields in sunspots are discussed, and the methods and equipment
used in measuring their field strengths and polarities are described in detail.
A scheme for classifying sunspots magnetically is given and all the spot-
groups observed from 1917 to 1924, inclusive, are classified for each day.
A law describing the magnetic properties of sunspots is deduced from the
observations.

Part II of this work comprises the daily magnetic observations of each
sunspot observed over the entire seven-year period. The observations are
recorded on drawings of the solar disk reproduced on a scale of seven inches
to the sun's diameter.

The publishing program of the Observatory also includes provision for
contributing minor articles and miscellaneous notes, too brief for inclusion
in the "Contributions" series, to issues of the Publications of the Astro-
nomical Society of the Pacific, which appear bi-monthly and which have a

OFFICE OF PUBLICATIONS 401

wide professional circulation. These articles, as reprints, are obtained for
Observatory use but are not distributed generally.

As with all Department heads, the Director of the Observatory sends an
annual report to the President of Carnegie Institution, which is published
in the Year Book of the Institution and distributed in reprint form to the
regular list of correspondents of the Observatory. The reports summarize
the scientific work of the year, including the activities in instrument design
and construction, and record the changes in organization and personnel.
Taken in their entirety these reports comprise a brief scientific history of
the Observatory.

THE DEPARTMENT OF TERRESTRIAL MAGNETISM

The Department of Terrestrial Magnetism was formally established in
1904 by the Institution in general accordance with a plan for an "Inter-
national Magnetic Bureau," submitted by Dr. Louis A. Bauer in 1902. The
purpose of the proposed bureau was "to investigate such problems of world-
wide interest as relate to the magnetic and electric conditions of the earth
and its atmosphere, not specifically the subject of inquiry of any one country
but of international concern and benefit."

Since its founding, the Department has been engaged in investigating the
phenomena of terrestrial magnetism and electricity, with the object of better
defining the laws which govern their manifestations and learning, if possible,
something of their nature and causes.

First, data from all parts of the earth were accumulated in order to obtain
a general picture of the magnetic and electric conditions and variations, on
the basis of which theoretical considerations could be more firmly built.
Accordingly, during the period 1905 to 1937 some 200 magnetic exploratory
expeditions were sent to remote and little-explored regions and to countries
in which either there were no established organizations for magnetic work
or existing agencies could not undertake such work and welcomed the co-
operation of the Department.

Magnetic and geographical data have thus been obtained at over 6000
stations. About 700 of these localities have been revisited, some of them
repeatedly, to determine the progressive changes in the direction and inten-
sity of the earth's magnetism. The problems presented by these so-called
secular variations are important particularly in connection with their pos-
sible indication of conditions in the earth's crust and interior.

Concomitantly with the land magnetic work a magnetic survey of the
oceans was undertaken, first in the Pacific Ocean, as, for that ocean particu-
larly, magnetic data were urgently needed for the correction of magnetic
charts and for the studies of investigators. During August 1905 to May
1908, three cruises were made with the chartered brigantine Galilee, aggre-
gating 63,834 nautical miles, or 73,511 statute miles.

The work at sea was done subsequently by a non-magnetic vessel, the
Carnegie, of special construction, built by the Institution. Launched at
Brooklyn, New York, June 12, 1909, she made seven cruises in all the
oceans between latitudes 80° north and 61° south. The Carnegie was de-

402 CARNEGIE INSTITUTION OF WASHINGTON

stroyed November 29, 1929, by an explosion while in the harbor of Apia,
western Samoa, when about one-half of her Cruise VII had been completed.
The magnetic and electric survey of the oceans had then been so far ad-
vanced that the Trustees of the Institution decided not to replace her.

The aggregate length of the Carnegie's seven cruises, August 1909 to
November 1929, was 297,579 nautical miles, or 342,681 statute miles; thus
the total combined length of the cruises of the Galilee and Carnegie was
about 16.5 times the earth's circumference.

As the earth's magnetic and electric conditions are subject to continual
change, the Department observes and records the changes at two magnetic
observatories in the Southern Hemisphere, where few such stations exist;
one of these is at Watheroo, Western Australia, the other near Huancayo,
Peru, at an elevation of about 11,000 feet above sea level.

At these observatories continuous registrations are obtained of the varia-
tions of the magnetic elements, of the potential gradient and electrical con-
ductivity of the atmosphere, of earth currents, of the ionization of the upper
atmosphere (the ionosphere), and of meteorological and radio phenomena.
Both observatories make special spectrohelioscopic observations daily and
at Huancayo seismographs (since 1932) for the three components, as also
a cosmic-ray meter (since 1935) , are continually recording. The ionospheric
records furnish data particularly useful for the study of the ionization of
the upper atmosphere and cosmic radiation in relation to correlations of
these phenomena with terrestrial magnetism and electricity.

Special investigations and experiments are made at the laboratories in
Washington on fundamental problems in the structure of matter, magnetism,
and electricity, and on the application of physical methods developed in the
laboratory to the investigation of geophysical phenomena concerned with
electricity and magnetism.

Among the more important items of this part of the program is the con-
tinued improvement of instrumental equipment for more intensive study of
the ionosphere by radio methods. Another important feature is the develop-
ment of laboratory sources of high voltage and high-voltage vacuum tubes
of special design for investigations of atomic and nuclear physics. Investi-
gations of this type bearing on the structure and reactions of atomic nuclei
are highly important in the problems of modern physics pertaining to the
general structure of matter. A knowledge of the atomic nucleus and of the
properties of the basic particles of which atoms are built is a necessary step
toward the understanding of the nature and laws of magnetism.

The results of these studies are made widely available through various
channels.

The Office of Publications of Carnegie Institution has published a series
of six quarto volumes entitled "Researches of the Department of Terrestrial
Magnetism." These volumes contain the results of all the magnetic obser-
vations made on land and sea during the period 1905 to 1926. Volumes VII
and VIII of the series, to contain the results obtained at the Huancayo and
Watheroo magnetic observatories, are nearing completion and will be pub-
lished shortly.

OFFICE OF PUBLICATIONS 403

In preparation is a series of quarto volumes on the oceanographic and
meteorological results obtained on the Carnegie, Cruise VII, 1928-1929. The
first three volumes will relate to physical and chemical oceanography (two
volumes) and to biological results. The fourth and fifth volumes will deal
with the biological results (one volume) and the meteorological results of
the cruise.

The published papers, of which over 1600 have appeared, bear upon all
phases of the varied activities of the Department. Taken together they
comprise a representative record of what has been done in terrestrial mag-
netism and electricity and kindred subjects during the past three decades.
Various technical journals afford the means whereby the papers prepared
by the Department staff are widely distributed. Among the journals making
generous use of this material are the following: Terrestrial Magnetism and
Atmospheric Electricity, the Physical Review, the Journal of the Institute
of Radio Engineers, Nature, Zeitschrift fur Geophysik, the Scientific
Monthly, Science.

The Statistics of Publications and the Bibliography follow.

404

CARNEGIE INSTITUTION OF WASHINGTON

STATISTICS OF PUBLICATIONS

The table which follows gives the Institution's yearly production of mono-
graphic publications, now totaling 728 volumes, comprising 213,442 pages
of printed matter.

Production of monographic publications

Year

Number of

volumes

issued

Number of
octavo
pages

Number of
quarto
pages

Total

number of

pages

1902 . . .
1903 . . .
1904 . . .
1905...
1906. ..
1907 . . .
1908 . . .
1909. . .
1910. . .
1911. . .
1912. . .
1913. . .
1914. . .
1915. . .
1916. . .
1917...
1918. ..
1919. . .
1920. ..
1921. . .
1922. . .
1923. . .
1924. . .
1925. . .
1926. . .
1927. ..
1928 . . .
1929. . .
1930. . .
1931...
1932 . . .
1933. . .
1934. . .
1935. . .
1936. ..
1937. . .
1938. ..

Total

3
3
11
21
19
38
28
19
29
30
23
29
23
23
35
21
17
29
23
18
24
20
17
24
14
17
15
12
15
14
16
22
13
9
13
25
16

46
,667
,843
,783
,166
,284
,843
,695
,274
,062
,981
,605
,978
,686
,478
,464
,073
,834
,962
,068
,566
,459
,665
,970
,552
,520
,495
,938
,096
,017
,155
,256
,030
,742
,395
,795
,489

1,445
1,288
3,428
2,485
1,212
4,831
1,670
2,044
2,752
1,934
1,466
2,430
2,691
1,120
2,431
3,710
1,398
2,039
604
834
1,277
850
2,089
1,044
452
844
1,343
2,588
1,370
1,206
813
1,745
1,975
1,068

1
2
5
4
9
7
4
8
6
6
9
6
6
11
7
4
8
7
5
6
7
5
5
5
6
5
5
4
5
4
5
4
2
5
4
4

46
,667
,877
,228
,454
,712
,328
,907
,105
,732
,025
,357
,912
,152
,908
,155
,193
,265
,672
,466
,605
,063
,499
,247
,402
,609
,539
,390
,940
,360
,743
,626
,236
,555
,140
,770
,557

728

152,932

60,510

213,442

In addition, during the year, the Institution has issued the following:
Thirteen numbers in its Supplementary Publication Series, comprising 13
articles, chiefly Institution lectures, totaling 227 printed pages, illustrated
with many cuts ; 12 numbers of the News Service Bulletin, totaling 94 printed
pages and carrying 72 illustrations; and 5 numbers of the Clip Sheet, con-

OFFICE OF PUBLICATIONS

405

taining 21 short articles relating to the work of the Institution, suitable for
use of the press.

Receipts from sales of publications

Year

Index
Medicus

Year
Book

Miscellaneous
Books

1903

$2,256.91

2,370.47

2,562.76

2,970.56

3,676.71

3,406.19

4,821.85

4,470.50

4,440.21

4,652.14

4,992.02

5,079.16

5,010.21

4,382.19

4,616.21

4,324.29

4,267.95

5,451.86

6,277.32

5,774.59

5,777.46

4,533.68

5,636.25

5,728.31

1 , 650 . 65

887.85

433.70

363 . 65

574.30

119.35

50.20

81.60

29.60

16.40

47.60

109.50

$29 . 25
52.85
44.75
37.60
56.50
99.65
73.01

100 . 70
85.50
61.65
75.95
49.65
47.60
46.60
51.55
21.10
93.30
40.50
50.55
59.25
70.10
31.00
25.00
41.40
59.67
87.80
41.74

127.85

159.38
80.60
69.89
50.31
73.28
71.10
88.10
94.80

1904

$12.75
431.44
1,341.52
2,292.89
4,371.67
6,287.21
5,899.05
6,366.55
6,782.34
7 , 140 . 69
6,273.59
5,239.98
8,115.37
7,253.59
5,575.61
8,476.33
12,901.43
10,356.64
8,248.00
7,994.20
7,429.53
8,019.49
8,269.31
8,322.10
9,948.60
8,450.47
8,977.44
7,749.05
5,086.28
4,294.83
4 , 500 . 60
4,118.52
5,639.99
4,528.49
4,866.75

1905

1906

1907

1908

1909

1910

1911

1912

1913

1914

1915

1916

1917

1918

1919

1920

1921

1922

1923

1924

1925

1926

1927

1928

1929

1930

1931

1932

1933

1934

1935

1936

1937

1938

Total

111,844.20

2,349.53

221,562.30

406 CARNEGIE INSTITUTION OF WASHINGTON

BIBLIOGRAPHY

Publications Issued by Carnegie Institution of Washington during

the Current Fiscal Year

Monographic Series

Year Book No. 36, 1937. Octavo, xxxiii + 66 + 430 pages, 1 plate, 6 text-figures.

No. 330 Hackett, C. W. Historical documents relating to New Mexico, Nueva Vizcaya,

and approaches thereto, to 1773. Collected by Adolph F. A. Bandelier and

Fanny R. Bandelier. Vol. III. Octavo, xii + 532 pp.
No. 338 Stock, Leo F. Proceedings and debates of the British Parliaments respecting

North America. Vol. IV, 1728-1739. Octavo, xxvii + 888 pp.
No. 469 Antevs, Ernst. Rainfall and tree growth in the Great Basin. (Edited by J. K.

Wright.) Octavo, vii + 97 pages, 2 plates, 7 text-figures.
No. 476 Contributions to Palseontology from Carnegie Institution of Washington. Mio-
cene and Pliocene Floras of Western North America. Octavo. (Papers I to III

were reported in Year Books Nos. 35 and 36.)

IV. Chaney, Ralph W. The Deschutes flora of eastern Oregon. Pages 185-
216, 7 plates.

V. Condit, Carlton. The San Pablo flora of west central California. Pages
217-270, 7 plates, 1 text-figure.

No. 487 Contributions to Palaeontology from Carnegie Institution of Washington. Octavo,
(Papers I to III were reported in Year Book No. 36.)
IV. Schultz, John R. A late Quaternary mammal fauna from the tar seeps

of McKittrick, California. Pages 111-215, 17 plates, 12 text-figures.
V. Howard, Hildegarde. The Rancho La Brea caracara: a new species.
Pages 217-240, 3 plates, 1 chart.

VI. Colbert, Edwin H. Pliocene peccaries from the Pacific Coast region of
North America. Pages 241-269, 6 plates, 4 text-figures.

VII. Laudermilk, J. D., and P. A. Munz. Plants in the dung of Nothrotherium
from Rampart and Muav Caves, Arizona. Pages 271-281, 11 plates, 1 text-
figure.
No. 490 Strain, Harold H. Leaf xanthophylls. Octavo, xi + 147 pages, 23 text-figures.
No. 491 Pearse, A. S., and Collaborators. Fauna of the eaves of Yucatan. Quarto,
iii + 304 pages, 8 plates, 306 text-figures.
This book contains the following papers:

Introduction. A. S. Pearse. Pages 1-17, 8 text-figures
I. Wolf, Frederick A. Fungal flora of Yucatan caves. Pages 19-21, 1
plate.
II. Hyman, Libbie H. Land planarians from Yucatan. Pages 23-32, 9
text-figures.

III. Stunkard, Horace W. Parasitic flatworms from Yucatan. Pages 33-50,
8 text-figures.

IV. Chitwood, B. G. Some nematodes from the caves of Yucatan. Pages
51-66, 45 text-figures.

V. Moore, J. Percy. Leeches (Hirudinea) from Yucatan caves. Pages
67-70, 2 text-figures.
VI. Pickford, Grace E. Earthworms in Yucatan caves. Pages 71-100, 3

plates, 16 text-figures.
VII. Chamberlin, Ralph V., and Wilton Ivie. Arachnida of the orders
Pedipalpida, Scorpionida, and Ricinulida. Pages 101-107, 17 text-figures.
VIII. Chamberlin, Joseph C. A new genus and three new species of false
scorpions from Yucatan caves (Arachnida-Chelonethida) . Pages 109-
121, 4 text-figures.
IX. Chamberlin, Ralph V., and Wilton Ivie. Araneida from Yucatan.
Pages 123-136, 24 text-figures.
X. Wharton, G. W. Acarina of Yucatan caves. Pages 137-152, 28 text-
figures.
XI. Copepoda from Yucatan caves. Pages 152-153.
XII. Furtos, Norma C. A new species of Cypridopsis from Yucatan. Pages

155-157, 1 text-figure.
XIII. Creaser, Edwin P. Larger cave Crustacea of the Yucatan Peninsula.
Pages 159-164, 8 text-figures.

OFFICE OF PUBLICATIONS 407

XIV. Chamberlin, Ralph V. Diplopoda from Yucatan. Pages 165-182,
55 text-figures.
XV. Mills, Harlow B. Collembola from Yucatan caves. Pages 183-190, 27
text-figures.
XVI. Hubbell, Theodore H. New cave crickets from Yucatan, with a re-
view of the Pentacentrinae, and studies on the genus Amphiacusta
(Orthoptera, Gryllidse). Pages 191-233, 78 text-figures, 2 graphs.
XVII. Banks, Nathan. A new myrmeleonid from Yucatan. Page 235.
XVIII. Pearse, A. S. Insects from Yucatan caves. Pages 237-249.

XIX. Wheeler, William Morton. Ants from the caves of Yucatan. Pages
251-255.
XX. Bequaert, J., and W. J. Clench. A third contribution to the molluscan
fauna of Yucatan. Pages 257-260.
XXI. Hubbs, Carl L. Fishes from the caves of Yucatan. Pages 261-295,
4 plates.
XXII. Gaige, Helen T. Some reptilian records from the caves of Yucatan.
Pages 297-298.

XXIII. Birds in Yucatan caves. Page 299.

XXIV. Mammalia from Yucatan caves. Pages 301-304.

No. 492 McKee, Edwin D. The environment and history of the Toroweap and Kaibab
formations of northern Arizona and southern Utah. Octavo, viii + 268 pages,
48 plates, 35 text-figures.
No. 494 Ritzman, Ernest G., and Francis G. Benedict. Nutrition physiology of the

adult ruminant. Octavo, vi + 200 pages, 3 plates, 3 text-figures.
No. 495 Gregory, William K., Milo Hellman, and G. Edward Lewis. Fossil anthro-
poids of the Yale-Cambridge India Expedition in 1935. Octavo, iii + 28 pages,
8 plates.
No. 496 Contributions to Embryology. Vol. XXVII, Nos. 160 to 169. Quarto, iv + 305
pages, 45 plates, 43 text-figures, 4 tables, 13 graphs.
This book contains the following papers:

Wislocki, George B., and George L. Streeter. On the placentation of the
macaque (Macaca mulatta), from the time of implantation until the forma-
tion of the definitive placenta. Pages 1-66, 13 plates, 1 text-figure. (Con-
tribution No. 160.)
Ramsey, Elizabeth M. The Yale embryo. Pages 67-84, 3 plates, 1 text-figure.

(Contribution No. 161.)
Brewer, John I. A human embryo in the bilaminar blastodisc stage (the Ed-
wards-Jones-Brewer ovum). Pages 85-93, 9 plates. (Contribution No. 162.)
Scipiades, Elemer, Jr. Young human ovum detected in uterine scraping.

Pages 95-105, 1 plate. (Contribution No. 163.)
Walmsley, Robert. Some observations on the vascular system of a female fetal
finback. Pages 107-178, 5 plates, 27 text-figures. (Contribution No. 164.)
SAglik, Saim. Ovaries of gorilla, chimpanzee, orang-utan and gibbon. Pages

179-189, 5 plates. (Contribution No. 165.)

Norris, Edgar H. The morphogenesis and histogenesis of the thymus gland in

man: in which the origin of the Hassall's corpuscles of the human thymus is

discovered. Pages 191-207, 7 plates, 1 text-figure. (Contribution No. 166.)

Berger, Charles A. Multiplication and reduction of somatic chromosome groups

as a regular developmental process in the mosquito, Culex pipiens. Pages

209-232, 1 plate, 10 text-figures. (Contribution No. 167.)

Arey, Leslie B. The history of the first somite in human embryos. Pages

233-269, 1 plate, 2 text-figures. (Contribution No. 168.)
Davenport, Charles B. Bodily growth of babies during the first post-natal
year. Pages 271-305, 1 text-figure, 4 tables, 13 graphs. (Contribution No.
169.)
No. 497 Benedict, Francis G., and Robert C. Lee. Hibernation and marmot physiology.

Octavo, x + 239 pages, 2 plates, 11 text-figures.
No. 499 Shattuck, George C, in collaboration with Joseph C. Bequaert, Margaret M.
Hilferty, Jack H. Sandground, Samuel D. Clark. A medical survey of
the Republic of Guatemala. Quarto, xi + 253 pages, 76 tables, 5 graphs, 2 plates,
1 text-figure.
No. 502 Wauchope, Robert. Modern Maya houses: a study of their archaeological sig-
nificance. Quarto, vii + 181 pages, 38 plates, 53 text-figures.
No. 503 Benedict, Francis G. Vital energetics: a study in comparative basal metab-
olism. Octavo, vii + 215 pages, 46 text-figures.

408 CARNEGIE INSTITUTION OF WASHINGTON

Supplementary Publications Series
No. 33 Our sample of the universe. Edwin P. Hubble. Octavo, 13 pages, 4 figures.
No. 34 Methods of inducing doubling of chromosomes in plants. A. F. Blakeslee and

Amos G. Avery. Octavo, 21 pages, 11 figures.
No. 35 The nature of solutions and their behavior under high pressures. It. E. Gibson.

Octavo, 17 pages, 9 figures.
No. 36 Core samples of the ocean bottom and their significance. Charles Snowden Piggot.

Octavo, 17 pages, 9 figures, 3 tables.
No. 37 The concept of uniformity. Frederick H. Seares. (Elihu Root Lecture Series)

Octavo, 50 pages.
No. 38 The raw materials of evolution. Theodosius Dobzhansky. Octavo, 5 pages.
No. 39 Utilitarian aspects of geophysics. A. G. McNish. Octavo, 13 pages, 9 figures.
No. 40 Prolactin, a product of the pituitary gland, and the part it plays in vital processes.

Oscar Riddle. Octavo, 17 pages, 11 figures.
No. 41 The forces which govern the atomic nucleus. M. A. Tuve. Octavo, 20 pages, 10

figures.
No. 42 Application of science in human affairs. John C. Merriam. Octavo, 11 pages.
No. 43 Climatic cycles and human populations in the Great Plains. Frederic E. Clements.

Octavo, 19 pages, 12 figures.
No. 44 Influence of science upon appreciation of Nature. John C Merriam. Octavo, 11

pages.
No. 45 Some aspects of cooperative research in history. John C Merriam. Octavo,

13 pages.

News Service Bulletins

Vol. IV, No. 23 An early chapter of earth history, by Norman E. A. Hinds. Pages 193

200, 4 figures.
No. 24 The shell structure of diatoms. Part I: Architectural and structural

design, by Paul S. Conger. Pages 201-208, 5 figures.
No. 25 The shell structure of diatoms. Part II: Industrial uses based on struc-
ture, by Paul S. Conger. Pages 209-216, 5 figures.

Maize and the Maya. Pages 217-224, 6 figures.

Pithecanthropus erectus — "the Ape-man of Java." Pages 225-232, 8

figures.

People and atmospheric ions, by G. R. Wait. Pages 233-240, 7 figures.

Earth physics, by A. G. McNlSH. Pages 241-248, 4 figures.

Recent discoveries relating to the antiquity of Man in America. Pages

249-256, 11 figures.
No. 31 Recent excavations in California. Part I: Early Man at Borax Lake, by

M. R. Harrington. Pages 257-261, 4 figures.
No. 32 Recent excavations in California. Part II: Product of the tar seeps

of McKittrick, by Chester Stock. Pages 262-264, 3 figures.
No. 33 The photosynthetic process. Pages 265-272, 1 color plate, 5 figures.
No. 34 Interpreting research in the Carnegie Institution of Washington. Pages

273-286, 10 figures.

Clip Sheet Service
No. 42 An effect of smoking

An extremely old fossil

The "Ape-man of Java"

The milpa system of Maya agriculture
No. 43 Primitive plants in Grand Canyon walls

Condensation-nuclei of the air

High metabolism of the Maya Indians

Diatoms
No. 44 Food-plants of the Maya

Atmospheric particles

Interpreting research results

Rarity of pre-Cambrian fossils
No. 45 Contact with great realities

Basal metabolism

Digestive efficiency of animal species

Role of drinking-water among animals
No. 46 Contributions of scientific research

The caves of Yucatan

Counting condensation-nuclei

General values of astronomy

Cud-chewing animals

No.

OFFICE OF PUBLICATIONS 409

Publications by the Institution Staff Issued through All Channels

during the Current Year

DIVISION OF ANIMAL BIOLOGY

Department of Embryology

Arey, L. B. The history of the first somite in human embryos. Carnegie Inst. Wash.

Pub. No. 496, Contr. to Embryol., vol. 27, pp. 233-269 (1938).
Ball, J. Sex activity of castrated male rats increased by estrin administration. Jour.

Comp. Psychol., vol. 24, pp. 135-144 (1937).
A case of apparent imitation in a monkey. Jour. Genetic Psychol., vol. 52, pp.

439-442 (1938).
Berger, C. A. Multiplication and reduction of somatic chromosome groups as a regular

developmental process in the mosquito, Culex pipiens. Carnegie Inst. Wash. Pub.

No. 496, Contr. to Embryol., vol. 27, pp. 209-232 (1938).
Bronk, D. W., S. S. Tower, D. Y. Solandt, and M. G. Larrabee. The transmission of

trains of impulses through a sympathetic ganglion and in its postganglionic nerves.

Amer. Jour. Physiol., vol. 122, pp. 1-15 (1938).
Brooks, C. McC, and I. Gersh. Pericellular nerve fiber terminations in the pars nervosa

and pars distalis of the rat's pituitary. Anat. Rec, vol. 70, suppl. 3, pp. 10-11 (1938).
Buck, J. B. Spectral composition of the light emitted by Jamaican fireflies. Anat. Rec,

vol. 70, suppl. 1, p. 114 (1937).
Altitudinal distribution of fireflies in Jamaica. Anat. Rec, vol. 70, suppl. 1, pp.

135-136 (1937).

Growth and development of the salivary gland chromosomes in Sciara. Proc.

Nat. Acad. Sci., vol. 23, pp. 423-428 (1937)

Clark, D. A. See Howe, H. A.

Crouse, H. V., and H. Smith-Stocking. New mutants in Sciara and their genetic be-
havior. Genetics, vol. 23, pp. 275-282 (1938).

De Garis, C. F. Branches of the aortic arch in 153 rhesus monkeys (second series) . Anat.
Rec, vol. 70, pp. 251-262 (1938).

Duel, A. B. See Howe, H. A.

Fitz-Gerald, P. A. On a developmental problem presented by the brain of a mentally
defective child. Anat. Rec, vol. 70, suppl. 3, p. 27 (1938).

Flexner, L. B. A thermodynamic analysis of ultrafiltration. The ultrafiltration of su-
crose and colloidal solutions. Jour. Biol. Chem., vol. 121, pp. 615-630 (1937).

and R. D. Stiehler. Biochemical changes associated with onset of secretion in

the fetal chorioid plexus. Evidence of a secretory mechanism. Anat. Rec, vol. 70,
suppl. 3, pp. 27-28 (1938).

Forbes, T. R. Studies on the reproductive system of the alligator. II: The effects of pro-
longed injections of cestrone in the immature alligator. Jour. Exper. Zool., vol. 75,
pp. 335-367 (1938).

Administration of cestrone to young alligators. Science, vol. 87, p. 282 (1938).

The effects of prolonged injections of testosterone in recently hatched alligators.

Anat. Rec, vol. 70, suppl. 3, p. 28 (1938).

Studies on the reproductive system of the alligator. I: The effects of prolonged

injections of pituitary whole gland extract in the immature alligator. Anat. Rec,
vol. 70, pp. 113-137 (1937).
Gersh, I. Relation of histological structure to the active substance extracted from the
posterior lobe of the hypophysis. Proc. Assoc. Research in Nervous and Mental
Diseases, vol. 17, pp. 433-436 (1936).

"Glandular" cells in the pars nervosa and stalk of the hypophysis. Proc. Soc

Exper. Biol, and Med., vol. 37, pp. 395-396 (1937).

■ Distribution of chloride in the gastric mucous membrane of the dog. Proc. Soc

Exper. Biol, and Med., vol. 38, pp. 70-72 (1938).

Improved histochemical methods for chloride, phosphate-carbonate and potassium

applied to skeletal muscle. Anat. Rec, vol. 70, pp. 311-329 (1938).

Histochemical studies on the fate of colloidal calcium phosphate in the rat. Anat.

Rec, vol. 70, pp. 331-349 (1938).

The fate of colloidal calcium phosphate in the dog. Amer. Jour. Physiol., vol. 121,

pp. 589-594 (1938).

Parenchymatous cells of the infundibular process and stalk in the rat. Anat.

Rec, vol. 70, suppl. 3, p. 93 (1938).

410 CARNEGIE INSTITUTION OF WASHINGTON

Gersh, I. See Brooks, C. McC.

Gey, G. O. Some problems in the maintenance of tissue cultures of endocrine organs to be

used for transplantation purposes in cases of specific endocrine deficiency. Anat. Rec,

vol. 70, suppl. 3, pp. 30-31, 93 (1938).
Hartman, C. G. Menstruation inhibiting action of testosterone. Proc. Soc. Exper. Biol.

and Med., vol. 35, pp. 87-89 (1937).

Alleged birth of triplets in the rhesus monkey. Science, vol. 87, p. 552 (1938).

Direct observation of menstruation in intraocular transplants of endometrium

by the method of Markee. Les Hormones Sexuelles (compt. rend, par L. Brouha,
Paris, 1938), p. 114.

Development and implantation of the monkey embryo. Les Hormones Sexuelles

(compt. rend, par L. Brouha, Paris, 1938), pp. 114-115.

Menstruation without ovulation (pseudomenstruation) : Incidence and treatment,

with special reference to the rhesus monkey. Les Hormones Sexuelles (compt. rend,
par L. Brouha, Paris, 1938), pp. 103-113.

Pregnancy in the monkey continues after castration. Anat. Rec, vol. 70, suppl.

3, p. 35 (1938)
Heuser, C. H. Early differentiation of the cells of the ovum in the rhesus monkey. Anat.

Rec, vol. 70, suppl. 3, p. 36 (1938).
Howe, H. A., and D. A. Clark. Fiber action potentials in the spinal cord of the cat. Amer.

Jour. Physiol, vol. 119, pp. 567-573 (1937).

S. T. Tower, and A. B. Duel. Facial tic in relation to injury of the facial

nerve. An experimental study. Arch. Neurol, and Psychiatry, vol. 38, pp. 1190-1198
(1937).

Howell, A. B. Morphogenesis of the shoulder architecture. Part VI: Therian Mammalia.
Quart. Rev. Biol., vol. 12, pp. 440-463 (1937).

Morphogenesis of the shoulder architecture: Aves. Auk, vol. 54, pp. 364-375 (1937).

Muscles of the avian hip and thigh. Auk, vol. 55, pp. 71-81 (1938).

Morphogenesis of the architecture of hip and thigh. Jour. Morphol., vol. 62, pp.

177-218 (1938).

Langworthy, O. R. See Ries, F. A.
Larrabee, M. G. See Bronk, D. W.

Lewis, M. R. Studies on the hypophysis cerebri by means of tissue cultures. Proc. Assoc.
Research in Nervous and Mental Diseases, vol. 17, pp. 463-465 (1936).

and E. G. Lichten stein. Studies on the transplantability of induced and spon-
taneous tumors occurring in mice of pure inbred strains. Growth, vol. 1, pp. 375-383
(1937).

Lewis, W. H. The cultivation and cytology of cancer cells. Amer. Assoc Adv. Sci.,
Occas. Pub. No. 4, pp. 119-120 (1937).

Lymphocytes and monocytes in tissue cultures of lymph nodes. Anat. Rec, vol. 70,

suppl. 3, p. 51 (1938).

Lichtenstein, E. G. See Lewis, M. R.

Mendelsohn, W. The cultivation of adult rabbit testicle in roller tubes. Anat. Rec,

vol. 69, pp. 355-359 (1937).
Metz, C. W. Small deficiencies and the problem of genetic units in the giant chromosomes

Genetics, vol. 22, pp. 543-556 (1937).

A note on salivary chromosome knots in relation to problems of mutation and

chromosome structure. Cytologia, Fujii jubilee vol., pp. 614-616 (1937).

Structure of the "puffed" regions in giant salivary gland chromosomes in Sciara.

Genetics, vol. 23, pp. 159-160 (1938).

Sciara reynoldsi: a new species which hybridizes with Sciara ocellaris. Comst.

Jour. Heredity, vol. 29, pp. 176-178 (1938).

Preliminary observations on Sciara hybrids. Jour. Heredity, vol. 29, pp. 179-186

(1938).
Norris, E. H. The morphogenesis and histogenesis of the thymus gland in man: in which

the origin of Hassall's corpuscles of the human thymus is discovered. Carnegie Inst.

Wash. Pub. No. 496, Contr. to Embryol., vol. 27, pp. 191-207 (1938).
Ramsey, E. M. The Yale embryo. Carnegie Inst. Wash. Pub. No. 496, Contr. to Embryol.,

vol. 27, pp. 67-84 (1938).
Ries, F. A., and O. R. Langworthy. A study of the surface structure of the brain of the

whale (Balasnoptera physalus and Physeter catadon). Jour. Comp. Neurol., vol. 68,

pp. 1-47 (1937).
SAglik, S. Ovaries of gorilla, chimpanzee, orang-utan and gibbon. Carnegie Inst. Wash.

Pub. No. 496, Contr. to Embryol., vol. 27, pp. 179-189 (1938).
and E. Scipiades, Jr. Study of the Gilfillen-Gregg skin test for pregnancy.

Endocrinology, vol. 21, pp. 684-686 (1937).

OFFICE OF PUBLICATIONS 411

Sohultz, A. H. Proportions, variability and asymmetries of the long bones of the limbs

and the clavicles in man and apes. Human Biol., vol. 9, pp. 281-328 (1937) .
■ To Asia after apes. Johns Hopkins Alumni Mag., vol. 26, pp. 37-46 (1938).

The number of vertebras and relative length of the spinal regions in primates.

Anat. Rec, vol. 70, suppl. 3, pp. 70-71 (1938).

Scipiades, E., Jr. Young ovum detected in uterine scraping. Carnegie Inst. Wash. Pub.

No. 496, Contr. to Embryol., vol. 27, pp. 95-105 (1938).

■ See Saglik, S.

Smith-Stocking, H. See Crouse, H. V.

Solandt, D. Y. See Bronk, D. W.

Stiehler, R. D. See Flexner, L. B.

Straus, W. L., Jr. The visceral anatomy of an infant chimpanzee. Jour. Mammal.,

vol. 18, pp. 501-507 (1937).
Streeter, G. L. Origin of the yolk-sac in primates. Anat. Rec, vol. 70, suppl. 1, pp.

53-54 (1937).

Origin of the gut endoderm in macaque embryos. Anat. Rec, vol. 70, suppl. 3,

p. 76 (1938).

See Wislocki, G. B.

Tower, S. S. Tropic control of non-nervous tissues by the nervous system: a study of
muscle and bone innervated from an isolated and quiescent region of spinal cord.
Jour. Comp. Neurol., vol. 67, pp. 241-267 (1937).

See Bronk, D. W.; Howe, H. A.

Walmsley, R. Some observations on the vascular system of a female fetal finback.

Carnegie Inst. Wash. Pub. No. 496, Contr. to Embryol., vol. 27, pp. 107-178 (1938).
Weed, L. H. Meninges and cerebrospinal fluid. Jour. Anat. (Brit.), vol. 72, pp. 181-215

(1938).
Wislocki, G. B., and G. L. Streeter. On the placentation of the macaque (Macaca

mulatta), from the time of implantation until the formation of the definitive placenta.

Carnegie Inst. Wash. Pub. No. 496, Contr. to Embryol., vol. 27, pp. 1-66 (1938).

Department of Genetics

Avery, A. G. See Blakeslee, A. F.; Satina, Sophia.

Bates, Robert W. Methods for the assay of prolactin. Cold Spring Harbor Symposia on
Quant. Biol., vol. 5, pp. 191-197 (1937).

and O. Riddle. Preparation of prolactin free from other pituitary hormones and

preparation of a mixture of other pituitary hormones free from prolactin. (Abstract)
Jour. Biol. Chem., vol. 123 (Proc), p. v. (May 1938).

See Riddle, Oscar; Schooley, J. P.

Bergner, A. D. See Blakeslee, A. F.
Blakeslee, A. F. Dedoublement du nombre de chromosomes chez les plantes par traite-
ment chimique. Compt. rend. Acad. Sci., vol. 205, no. 11, pp. 476-479 (Sept. 1937).

Studies in the behavior of chromosomes. U. S. Dept. Agric Yearbook Separate

No. 1605, pp. 1-35 (Dec. 1937).

■ Colchicine. Teaching Biologist, vol. 7, no. 4, p. 52 (Jan. 1938).

and A. G. Avery. Methods of inducing chromosome doubling in plants by treat-
ment with colchicine. (Abstract) Science, vol. 86, p. 408 (Nov. 1937).

Methods of inducing doubling of chromosomes in plants by treatment with

colchicine. Jour. Heredity, vol. 28, no. 12, pp. 393-411 (Dec 1937).

and J. L. Cartledge. Induction of polyploids in Datura and other plants

by treatment with colchicine. (Abstract) Genetics, vol. 23, no. 1, pp. 140-141 (Jan.
1938).

A. D. Bergner, and A. G. Avery. Geographical distribution of chromosomal prime

types in Datura stramonium. Cytologia, Fujii jubilee vol., pp. 1070-1093 (Aug. 1937).

See Satina, Sophia.

Cartledge, J. L. See Blakeslee, A. F.
Cauthen, G. E. See Riddle, Oscar.

Demerec, M. Relationship between various chromosomal changes in Drosophila melano-
gaster. Cytologia, Fujii jubilee vol., pp. 1125-1132 (Aug. 1937).

Frequency of spontaneous mutations in certain stocks of Drosophila melanogaster.

Genetics, vol. 22, pp. 469-478 (Sept. 1937).

Hereditary effects of X-ray radiation. Radiology, vol. 30, pp. 212-220 (Feb. 1938) .

and Helen Sllzynska. Mottled white 258-18 of Drosophila melanogaster.

Genetics, vol. 22, pp. 641-649 (Nov. 1937)
— See Kaufmann, B. P.

412 CARNEGIE INSTITUTION OF WASHINGTON

Dotti, Louis B. See Riddle, Oscar.

Hoover, Margaret E. A tandem inversion in Drosophila melanogaster. Genetics, vol.
22, pp. 634-640 (Nov. 1937).

Cytogenetic analysis of nine inversions in Drosophila melanogaster. Ztschr. f . ind.

Abst. Vererb., vol. 64, pp. 420-434 (1938).

Kaufmann, B. P. Morphology of the chromosomes of Drosophila ananassce. Cytologia,
Fujii jubilee vol., pp. 1043-1055 (Aug. 1937).

Complex chromosomal rearrangements following X-radiation of sperm of Drosophila

melanogaster. (Abstract) Genetics, vol. 23, no. 1, p. 154 (Jan. 1938).

Nucleolus-organizing regions in salivary gland chromosomes of Drosophila melano-
gaster. Ztschr. f. Zellforsch, u. mikr. Anat., vol. 28, no. 1, pp. 1-11 (Apr. 1938).

and M. Demerec. Frequency of induced breaks in chromosomes of Drosophila

melanogaster. Proc. Nat. Acad. Sci., vol. 23, no. 9, pp. 484-488 (Sept. 1937)
Lahr, Ernest L., and 0. Riddle. Proliferation of crop-sac epithelium in incubating and

in prolactin-injected pigeons studied with the colchicine method. (Abstract) Proc.

Amer. Physiol. Soc, 50th meeting, p. 124 (Mar. 1938).
Laughlin, Harry H. Race conditions in the United States. Amer. Year Book for 1937,

pp. 540-545 (1938).
A preliminary outline proposed for development into Report No. I of the Survey of

the Human Resources of Connecticut. 37 pp. (mimeographed) . Eugenics Rec. Office,

Dept. Genetics (Oct. 1937).

Clinical studies in human heredity, sees. 1, 2, 3. 132 pp. (mimeographed).

Eugenics Rec. Office, Dept. Genetics (1938).
MacDowell, E. C. See Potter, James S.
Potter, James S., M. J. Taylor, and E. C. MacDowell. Transfer of acquired resistance

to transplantable leukemia in mice. Proc. Soc. Exper. Biol, and Med., vol. 37, pp.

655-656 (1938).

See Victor, Joseph.

Richter, M. N. Similarities and differences between leukemic lymphocytes and tumor cells
in mice. (Abstract) Anat. Rec, vol. 70, no. 4, suppl. 3, p. 66 (Mar. 1938).

Riddle, Oscar. The hormones of the anterior pituitary. Ohio. Jour. Sci., vol. 37, no. 6,
pp. 446-463 (Nov. 1937).

■ Physiological responses to prolactin. Cold Spring Harbor Symposia on Quant.

Biol., vol. 5, pp. 218-228 (1937).

On carbohydrate metabolism in pigeons. Cold Spring Harbor Symposia on Quant.

Biol., vol. 5, pp. 362-374 (1937).

Progress in forming a National Association of Biology Teachers. Teaching Biolo-
gist, vol. 7, no. 7, pp. 101-103 (Apr. 1938).

■ ■ Educational darkness and luminous research. Science, vol. 87, no. 2261, pp. 375-380

(Apr. 1938).
■ On anterior pituitary hormones. Sechenov Jour. Physiol. U. S. S. R., vol. 21,

no. 5-6, p. 61 (1938).
and R. W. Bates. Prolactin. Proc. Assoc, for Nervous and Mental Disease, vol. 17,

pp. 287-297 (Jan. 1938).

and G. E. Cauthen. Erythrocyte number in young pigeons and its relation to

heredity, growth and metabolism. Amer. Jour. Physiol., vol. 122, no. 2, pp. 480-485
(May 1938).

and Louis B. Dotti. A blood sugar increasing effect of parathyroid extracts.

(Abstract) Anat. Rec, vol. 70, no. 1, suppl., p. 63 (Dec. 1937).

The pituitary and sex hormones capable of increasing serum calcium and

some conditions affecting their action. (Abstract) Proc Amer. Physiol. Soc, 50th
meeting, pp. 171-172 (Mar. 1938).

See Bates, Robert W.; Lahr, Ernest L.; Schooley, J. P.

Satina, Sophia, and A. F. Blakeslee. Chromosome behavior in triploids of Datura
stramonium. I: The male gametophyte. Amer. Jour. Bot., vol. 24, no. 8, pp. 518-527
(Oct. 1937).

Chromosome behavior in triploid Datura. II: The female gametophyte.

Amer. Jour. Bot., vol. 24, no. 9, pp. 621-627 (Nov. 1937).

and A. G. Avery. Chromosome behavior in triploid Datura stramonium,

III: The seed. (Abstract) Genetics, vol. 23, no. 1, p. 165 (Jan. 1938),
Schooley, J. P. Pituitary cytology in pigeons. Cold Spring Harbor Symposia on Quant.

Biol., vol. 5, pp. 165-179 (1937).
and O. Riddle. The morphological basis of pituitary function in pigeons. Amer.

Jour. Anat., vol. 62, pp. 313-349 (Mar. 1938).
and R. W. Bates. A specific action of the anterior pituitary on the intes-

tine. (Abstract) Anat. Rec, vol. 70, no. 1, suppl., p. 61 (Dec. 1937)

OFFICE OF PUBLICATIONS 413

Slizynska, Helen. Salivary chromosome analysis of the white facet region of Drosophila
melanog aster. Genetics, vol. 23, pp. 291-299 (May 1938).

See Demerec, M.

Slizynski, B. M. Salivary chromosome studies of lethals in Drosophila melanogaster. Ge-
netics, vol. 23, pp. 283-290 (May 1938).

Steggerda, Morris. Testing races for the threshold of taste, with PTC. Jour. Heredity,
vol. 28, no. 9, pp. 309-310 (1937).

Taylor, M. J. See Potter, James S.

Victor, Joseph, and James S. Potter. The respiratory quotients of normal and leukemic
mouse lymphoid tissue. Amer. Jour. Cancer, vol. 32, no. 4, pp. 554-560 (Apr. 1938).

Influence of transmitted leukaemia on metabolism of uninfiltrated lymphoid

tissue. British Jour. Exper. Pathol., vol. 19, pp. 227-238 (1938).

Nutrition Laboratory

Benedict, Francis G. Race: A factor in human metabolism. Proc. Amer. Philos. Soc,

vol. 78, pp. 101-110 (1937).
■ ■ Vital energetics: A study in comparative basal metabolism. Carnegie Inst. Wash.

Pub. No. 503 (1938). vii -f 215 pp., 46 figs., 4 tables.
■ Lan-Chen Kung, and Stanley D. Wilson. The basal metabolism and urinary

nitrogen excretion of Chinese, Manchus, and others of the Mongolian race. Chinese

Jour. Physiol., vol. 12, pp. 67-100 (1937).

and Robert C. Lee. Die Bedeutung des Korperfettes fur die Warmebildung im

Organismus. Biochem. Ztschr., vol. 293, pp. 405-409 (1937).

Lipogenesis in the animal body, with special reference to the physiology

of the goose. Carnegie Inst. Wash. Pub. No. 489 (1937). ix + 232 pp., 30 figs., 35

tables.
Further observations on the physiology of the elephant. Jour. Mammal.,

vol. 19, pp. 175-194 (1938).
Hibernation and marmot physiology. Carnegie Inst. Wash. Pub. No. 497

(1938). x -f- 239 pp., 2 pis., 11 figs., 58 tables.

and Henry C. Sherman. Basal metabolism of rats in relation to old age and

exercise during old age. Jour. Nutrition, vol. 14, pp. 179-198 (1937)
See Ritzman, Ernest G.

Carpenter, Thorne M. The partition of urinary nitrogen of fasting and hibernating
woodchucks (Arctomys monax). Jour. Biol. Chem., vol. 122, pp. 343-347 (1938).

The effect of urea on the human respiratory exchange and alveolar carbon dioxide.

Jour. Nutrition, vol. 15, pp. 499-512 (1938).

and Carl G. Hartman. Effects of hexoses on the respiratory quotient of the rhesus

monkey. Amer. Jour. Physiol., vol. 123, p. 32 (1938) .

and Robert C. Lee. The effect of ingestion of alcohol on human respiratory ex-
change (oxygen consumption and R. Q.) during rest and muscular work. Arbeitsphy-
siologie, vol. 10, pp. 130-157 (1938).

The effect of muscular work on the amounts of alcohol in urine, expired

air, and blood, after its ingestion by man. Arbeitsphysiologie, vol. 10, pp. 158-171
(1938).

The effect of muscular work on the metabolism of man after the ingestion

of sucrose and galactose. Arbeitsphysiologie, vol. 10, pp. 172-187 (1938)
Hartman, Carl G. See Carpenter, Thorne M.
Kung, Lan-Chen. See Benedict, Francis G.
Lee, Milton O., and Robert C. Lee. Effects of thyroidectomy and thyroid feeding in

geese on the basal metabolism at different temperatures. Endocrinology, vol. 21, pp.

790-799 (1937).
Lee, Robert C. See Benedict, Francis G.; Carpenter, Thorne M.; Lee, Milton O.
Ritzman, Ernest G., and Francis G. Benedict. The nutritional physiology of the

adult ruminant. Carnegie Inst. Wash. Pub. No. 494 (1938). vi + 200 pp., 3 pis.,

3 figs., 55 tables.
Sherman, Henry C. See Benedict, Francis G.
Wilson, Stanley D. See Benedict, Francis G.

GEOPHYSICAL LABORATORY

Adams, Leason H. The freezing-point — solubility curves of hydrates and other compounds

under pressure. Amer. Jour. Sci., vol. 35A, pp. 1-18 (1938).
The Earth's interior: Its nature and composition. Smithsonian Report for 1937,

pp. 255-268 (1938).

414 CARNEGIE INSTITUTION OF WASHINGTON

Barth, Tom. F. W. Radium and the petrology of certain granites of Finland. Amer. Jour.
Sci., vol. 35A, pp. 231-245 (1938).

See Greig, J. W.

Bowen, Norman L. Lavas of the African Rift Valleys and their tectonic setting. Amer.
Jour. Sci., vol. 35A, pp. 19-33 (1938).

and J. F. Schairer. Crystallization equilibrium in nepheline-albite-silica mixtures

with fayalite. Jour. Geol., vol. 46, pp. 397-411 (1938).

See Schairer, J. F.

Burlew, J. S. See Morey, George W.

England, J. See Wright, F. E.

Fenner, Clarence N. Olivine fourchites from Raymond Fosdick Mountains, Antarctica.

Bull. Geol. Soc. Amer., vol. 49, pp. 367-400 (1938).
Contact relations between rhyolite and basalt on Gardiner River, Yellowstone

Park. Bull. Geol. Soc. Amer., vol. 49, pp. 1441-1484 (1938).

The phenomena of Falling Mountain. Amer. Jour. Sci., vol. 35A, pp. 35-48 (1938) .

Gibson, R. E. The nature of solutions and their behavior under high pressures. Scientific

Monthly, vol. 46, pp. 103-119 (1938).
On the effect of pressure on the solubility of solids in liquids. Amer. Jour. Sci.,

vol. 35A, pp. 49-69 (1938).

and John F. Kincaid. The influence of temperature and pressure on the volume and

refractive index of benzene. Jour. Amer. Chem. Soc, vol. 60, pp. 511-518 (1938)
Goranson, Roy W. High temperature and pressure phase-equilibria in the albite — water
and orthoclase — water systems. Trans. Amer. Geophys. Union, 19th ann. meeting,
pp. 271-273 (1938).

Silicate — water systems: Phase equilibria in the NaAlSi308 (albite) — H20 and

KAlSi308 (orthoclase) — H20 systems at high temperatures and pressures. Amer. Jour.
Sci., vol. 35A, pp. 71-91 (1938).

Greig, J. W., and Tom. F. W. Barth. The system, Na2O.Al203.2SiOa (nephelite, car-
negieite)— Na20.AL03.6Si02 (albite). Amer. Jour. Sci., vol. 35A, pp. 93-112 (1938).

Hibben, James H. The application of the Raman effect to petroleum chemistry. Re
printed from "The science of petroleum," pp. 1206-1212. New York, Oxford Univ.
Press (1938).

Some recent developments and applications of the Raman effect. Pub. Amer.

Assoc. Sci., Symposium No. 7 on "Recent advances in chemical physics" (1938).

The constitution of some boric oxide compounds. Amer. Jour. Sci., vol. 35A, pp.

113-125 (1938)

Ingerson, Earl. Uraninite and associated minerals from Haddam Neck, Connecticut.
Amer. Mineral., vol. 23, pp. 269-276 (1938).

Laboratory technique of petrofabric analysis. Part II of Memoir 6, Geol. Soc.

Amer., "Structural petrology," by E. B. Knopf and Earl Ingerson, pp. 209-262 (1938).

Summary of article by Bruno Sander: "Uber Zusammenhange zwischen

Teilbewegung und Gefiige in Gesteinen," Tschermak's Mineralog. Petrog. Mitt., vol.
30, pp. 281-314 (1911). Excerpt from "Report of the Committee on Structural
Petrology," Div. Geol. and Geog., Nat. Res. Council, pp. 23-31 (1938).

Albite trends in some rocks of the Piedmont. Amer. Jour. Sci., vol. 35A, pp. 127-

141 (1938).

See Morey, G. W.

Kincaid, John F. See Gibson, R. E.

Kracek, F. C, G. W. Morey, and H. E. Merwin. The system, water — boron oxide. Amer.

Jour. Sci., vol. 35A, pp. 143-171 (1938).
Ksanda, C. J., and G. Tunell. The unit cell and space-group of ^-glycine. Amer. Jour.

Sci., vol. 35A, pp. 173-178 (1938).

See Tunell, G.

Merwin, H. E., and E. Posnjak. Clays and other minerals from the deep sea, hot springs,
and weathered rocks. Amer. Jour. Sci., vol. 35A, pp. 179-184 (1938).

See Kracek, F. C; Tunell, G.

Morey, George W. The availability of optical glass in America. Jour. Optical Soc.
Amer., vol. 28, pp. 5-7 (1938).

Rock formation: Nature's chemical industry. Soc. Chem. Ind., vol. 57, pp. 966-

971 (1938).

The properties of glass. Amer. Chem. Monograph Ser. No. 77. 571 pp., 161 tables,

152 figs. New York, Reinhold (1938) .

and John S. Burlew. Studies of solubility in systems containing alkali and water.

I: General introduction. II: A filter autoclave for solubility measurements at elevated
temperatures and atmospheric pressure. Ill: Solubility of NaOH in a saturated
Na2C03 solution between 60 and 70° C. Amer. Jour. Sci., vol. 35A, pp. 185-215 (1938).

OFFICE OF PUBLICATIONS 415

Morey, George W., and Earl Ingerson. A bomb for use in hydrothermal experimentation.
Amer. Mineral., vol. 22, pp. 1121-1122 (1937).

The system, water — sodium disilicate. Amer. Jour. Sci., vol. 35A, pp. 217-

225 (1938).
See Kracek, F. C.

Piggot, Charles Snowden. Core samples of the ocean bottom and their significance.

Scientific Monthly, vol. 46, pp. 201-217 (1938).
The technique of securing undisturbed core-samples of the ocean bottom. Proc.

Amer. Phil. Soc, vol. 79, pp. 35-46 (1938).

Radium in rocks. V: The radium content of the four groups of pre-Cambrian

granites of Finland. Amer. Jour. Sci., vol. 35A, pp. 227-229 (1938)
Posnjak, E. The system, CaS04— H20. Amer. Jour. Sci., vol. 35A (1938).

See Merwin, H. E.

Roberts, Howard S. Direct measurement of silicate heats of melting. Amer. Jour. Sci.,

vol. 35A (1938).
Sohairer, J. F., and N. L. Bowen. The system, leucite — diopside — silica. Amer. Jour.

Sci., vol. 35A (1938).

See Bowen, Norman L.

Shepherd, E. S. The gases in rocks and some related problems. Amer. Jour. Sci., vol. 35A

(1938).
Sosman, Robert B. Evidence on the intrusion-temperature of peridotites. Amer. Jour.

Sci., vol. 35A (1938).
Tunell, G., H. E. Merwin, and C. J. Ksanda. The crystallography of potassium tetra-

thionate. Amer. Jour. Sci., vol. 35A (1938).

See Ksanda, C. J.

Wright, F. E., and J. L. England. An improved torsion gravity meter. Amer. Jour. Sci.,

vol. 35A (1938).
Zies, E. G. The concentration of the less familiar elements through igneous and related

activity. Chem. Rev., vol 23, pp. 47-64 (1938).

Surface-manifestations of volcanic activity. Trans. Amer. Geophys. Union, 19th

ann. meeting, pp. 10-23 (1938).

The concentration of the less familiar elements through igneous and related activ-

ity. Amer. Jour. Sci., vol. 35A (1938)

DIVISION OF HISTORICAL RESEARCH

Adams, Eleanor B. See Scholes, France V.

Burnett, Edmund C. The Continental Congress; The Provincial Congresses; United States

of America (origin of the name) . In Dictionary of American History. New York,

Scribner (1938).
The "More Perfect Union": the Continental Congress seeks a formula. Catholic

Hist. Rev., vol. 24, pp. 1-29 (Apr. 1938).

Southern statesmen and the Confederation. North Carolina Hist. Rev., vol. 14,

pp. 343-360 (Oct. 1937)
Chamberlain, Robert S. A report on colonial materials in the governmental archives of

Guatemala City. In Handbook of Latin American Studies, pp. 387-432. Cambridge,

Harvard Univ. Press (1937). Also reprinted separately.
Hackett, Charles W. Historical documents relating to New Mexico, Nueva Vizcaya, and

approaches thereto, to 1773. Vol. III. Carnegie Inst. Wash. Pub. No. 330 (Jan. 1938).
Harrison, Margaret W. List of doctoral dissertations in history now in progress at

American universities, 1937. Division of Historical Research, Carnegie Inst. Wash.

(Jan. 1938).
Heidel, W. A. Review of Wilko De Boer, "Galeni De Propriorum Animi Cuiuslibet

Affectuum Dignotione et Curatione, De Animi Cuiuslibet Peccatorum Dignotione et

Curatione, De Atra Bile." Amer. Jour. Philol., vol. 59, p. 253 (Apr. 1938).
Menendez, Carlos R. See Scholes, France V.
Pearse, A. S. Fauna of the caves of Yucatan. Carnegie Inst. Wash. Pub. No. 491 (June

1938).
Pogo, Alexander. The limit of visibility of penumbral lunar eclipses. Pop. Astron.,

vol. 45, pp. 349-352 (1937).

Classification of solar and lunar eclipses. Pop. Astron., vol. 45, pp. 540-549 (1937) .

The partial lunar eclipse of 1937 November 18. Pop. Astron., vol. 46, pp. 76-78

(1937).

Additions and corrections to Oppolzer's Canon der Mondfinsternisse. Astron.

Jour., vol. 47, pp. 45-48 (1938).

The solar eclipse of 1938 May 29 — the first umbral eclipse of its saros series. Pop.

Astron., vol. 46, pp. 256-259 (1938).

416 CARNEGIE INSTITUTION OF WASHINGTON

Redfield, Robert. The coati and the ceiba. Maya Research, vol. 3, pp 231-244 (1937).

The second epilogue to Maya history. Hispanic Amer. Hist. Rev., vol. 17, pp. 170-

181 (1937).

(with R. C. Jones) . Middle America: Ethnology. In Handbook of Latin American

Studies, pp. 12-18. Cambridge, Harvard Univ. Press (1937)
Ricketson, O. G., Jr., and Edith B. Ricketson. Uaxactun, Guatemala, Group E — 1926-

1931. Carnegie Inst. Wash. Pub. No. 477 (Sept. 1937).
Rubio Mane, J. Ignacio. El concepto historico de capitania general. Revillagigedo y

Yucatan (pamphlet). Merida (1938).

Los piratas Lafitte. Mexico (1938).

Numerous articles on historical subjects in Diario de Yucatan, Merida, and Excel-
sior, Mexico City.

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